There is not much we can comment on since you actually posted your own (correct) solution. You can follow this build guide:
http://www.gamesas.com/topic/1342463-complete-character-design-freedom-damage-resist-caps-and-ridiculous-damage-thread-10/
Completion of a character build on the synergy of skills as discribed in the above will trivialize enemy encounters even on master difficulty.
Interesting post, might keep that in mind

You didn't say which platform,but my husband went out and bought a new controller for his ps3 and it make's life a whole lot easier for him. it's a little heavier and the button's and such are a little bit further apart. ( he only wishes they had a nice heavy controller like I have for the x-box)
I know you said he played other games, but sometime goofy little stuff help's.
I had to turn the controller sensitivity down for RDR when I played, cause I would swing wide of the mark to fast. I also turned the brightness down, that was one bright game.
It's mentioned between the lines, but we play on xbox

but nevertheless, you're quite right about goofy little stuff

Also , in RDR, he overcame that by using 'dead eye' to its full extent. (smart man don't you think ^^)
I'm at your dad's age, but I play PC so it is a "little" bit easier for me. I play Adept as well, possibly all what we old folks can handle.

I figured out one thing though, not sure if that is common play by the halfgods on here. Just save the game before the cave, then sneak and sit a good arrow in the head of someone, then call out the atronarch, sneak back into the best shadow there is and you might even kill one of those Dreadlords. Save all the time. What I'm saying is, if you don't have the fastness and the flexibility in your hands anymore, go sneaky.
I'm over lvl 20 now and monsters are becoming really hard sometimes, but I use my sneak to win those fights...and my flame atronarch. And I climb mountain walls or even run into the river to survive. But I'm fine with that, because my char is pretty weak and I do anything to save him, without having to load another save.
Wish I had some better help by now, but only 40 in Con. Met a silly Conjurer, sending frigging Frost atronarchs at me, I can't even find that spell?
Experience from a similar point of view is always interesting. And he follows a part of your advice now, he softens up the enemy with arrows, then goes in with the sword. And he does save a lot

He should get the knack eventually! Thats what I do take my time maybe go on easier until he gets it??
He does, but his learning curve is sometimes a little lengthy

A warrior or tank build is good to start off with, try and get him in the habit of countering his swing with the look thumb stick ( if your swing to the left, counter by slightly looking right) just like in RL your char, ends up looking in the direction of the swing and by countering you keep your "eye on the ball" as it where. Try and get him to turn down difficulty ( I know adept isn't that hard) until he gets the hang of combat.Pay attention to all conversation, cause if you don't the amount of quests and side quests you can amass can get quite overwhelming for a newbie.And lastly... tell him to explore and have fun! He doesn't have to rush anything and can go at his own pace, there is no time limit on any quest/side quest but mostly HAVE FUN and experiment to find a build that best fits his play style and personality.
He was already on that build (being a barbarian whenever possible in games). I suggested your pointing technique, but it sometimes make it more confusing for him. But that can be because of our old controller ^^ me and my brother also guide him a little when it comes to choices in-game, and leave the fun parts for him. And don't worry, if I see him playing, he's having the time of his life (you know, sort of

)
That is the first thing I did and it helped me a lot.
Is his problem that he cannot work the controller well enough to deal with the "action" elements of the game, or is it that he is overwhelmed by not knowing what to do next in such a large world with so many quests and stuff? If it is the "action" part, then maybe he would enjoy one of the prior games (Oblivion or Morrowind) since both of those were easier in terms of hand/eye coordination, twitch skills, etc.
EDIT: another thing you could do if it is the "action" part of the game that is giving him trouble is sneak in and turn the difficulty setting of his game down a notch or two when he is not looking.
It's the action part mostly, he's very good with the quest journal, so he can keep tabs on his activities. He's experimenting now with the sensitivities, so I'll let him decide what suits him best. And turning the difficulty down unnoticed, that would be hard. First of all, in our family, sneaky things are frowned upon

and he'd notice too

He may also like Fallout/New Vega. It is an RPG, open in concept like some of the games he likes, but VATS makes combat easier. It is one of my dad's favorite games, next to Read Dead Redemption. BTW, he is 72.
However, have your dad try out different controllers and different controller sensitivity. You might also build a character for him, one that is basically a tank so that combat does not kill him as fast. Or, show him how to do it. This is a perfect case where building an uber character might be a good thing. That way he can concentrate on the story and the quests and combat is more a diversion.
Oh my, that's a game I forgot to mention, he played fallout 3 as well as new vegas. Indeed, he does mention that a VATS system in Skyrim would've been great for him, as he used it extensively too. Due to me and my brother's guidance, we're fleshing out a character that's not overpowered, but going in that direction. And dad's just fine with that ^^ good advice though.
agree with CCNA the VATS in fallout is much easier and still fun to play....other than that sensitivity down can help. I prefer it in Skyrim since it isn't like you are playing an fps and spinning slow can get you killed. I also like to fight in 3rd person sometimes so he could try that the small field of view in first person makes even a seasoned gamer have to look around to see where that enemy went.
3rd person fighting is a little out of his league, since he got no sense of where he's hitting, although it's almost the same middle like in 1st person. He just can't adapt

But I'll try to give some pointers in that direction.
I kind of know the troubles he might be having. The combat system does not lock your character's focus onto a target like most other games do in combat. So one can easily run completely past a target with an attack. It can be very annoying, when you think you want to "hit this guy" and then have no idea how you could possibly have missed it. So here is some advise:
- Increase the sensitivity of your mouse in the settings. It will help when an attack misses a target and lets you turn around and aim quicker.
- Turn off mouse acceleration in the SkyrimPrefs.ini file. You find the option in your home directory under "My Documents\My Games\Skyrim". It is called bMouseAcceleration=0 and can be found in the "[Controls]" section.
- Learn how to fight with one- and two-handed weapons. Find easy targets, like wolves and weak bandits. Do not mind when you die but just reload until you are satisfied with your progress.
- Alternatively, learn to do sneak attacks with daggers and bows. Being able to one-shot or one-hit a target with a well-planned sneak attack spares one from a few melee fights, decimates the opponents and is just as rewarding.
- Alternatively, learn how to block with shield and two-handed weapons and take your time with your targets.
- Use the shout Slow Time. It will effectively slow down the time and make combat a lot easier for a few seconds.
As replied in the first answer, we're on xbox. Still kind of you for the step-for-step guide ^^ Indeed, although heavy armoured, he's sneaking a little, and his first arrow shot softens up a lot of enemies, thusly shortening encounters. He does block, but he has always been more the "club first then defend" kind of player. Using/ telling him where to find the shout, that didn't cross my mind, good one
Thanks for all the replies people, you can be sure I'll put them to good use