I'm all very new to magic in Skyrim, so any answers to the below would be great:

1. Am i right that the more powerful a spell (as in, the more magicka it uses) the greater the skill increase it gives you? For example, even though they're so similar casting Magelight is a faster way to level Alteration than Candlelight?

2. In terms of defence, what's better; the shield or ward spells? I know the former is for melee damage and the latter for magic; but it seems every time I use ward it just gets destroyed and I used too much magicka creating it. I'm better just going on the attack, I think...

3. Is there any possible way to remove the enchantment from an item without destroying it, even if it's a glitch? I want to remove the enchantment from a pair of unique boots; and there's no console-able version I can give myself.

4. Can you explain the 'level' aspect of certain spells - particularly those in Illusion etc. I remember in Oblivion the 'level' of the enemy gave you a false impression of how high they would work until; if it said level 20 it would work on everything, for example. Is it the same in Skyrim?

5. Is there any real point to Illusion? I've never used the fear/frezy type of spells before, but I'm tempted.

Sorry for the list; I'm just new and stuck! Thanks.

I can't answer most of your questions, as I use a mod that changes magic around, and I don't want to give answers and then have it turn out that it's different for me because of the mod.

However, I can address two of your questions:

2. In terms of defense, I would not rely only on ward spells. They can be useful on occasion, but in general, you're better off simply dodging whatever spell is coming at you and saving your magicka to cast a spell in retaliation.

5. I think a lot of people undervalue Illusion. If your mage is pumping Magicka exclusively and not adding anything to health, a Calm or Fear spell can be invaluable in saving your life. Or sneak up and Frenzy an enemy and make them fight their own colleagues. Muffle and Invisibility are very helpful for dungeon crawling undisturbed, although I seem to remember that Invisibility is very expensive, mana-wise, in the vanilla game. I've found Courage, Rally and Call to Arms helpful as well--Courage for followers (not that they flee easily, but the extra health and stamina are very useful), and Rally/Call to Arms for groups-- especially helpful in a few specific quests which I won't spoil for you!

You'll probably get more (and better) answers to your question if you post this in the spoilers forum. Some of your questions will require at least borderline spoilers to answer properly. Just hit report on your post, and then ask the mods to move it to the spoilers forum.