As it's been said, bashing is nice. If you're any good with the Block skill (even if you're using two handed weapons), you can deal good damage and even disarm your opponents, and there's little better crowd control than outright disarming folks.
For two handed weapons, invest in Sweep. It's an awesome skill that can stagger a load of enemies in a decent range if it doesn't outright kill most of them; it really turns the tables for you.
If you're dual wielding and can't block (and sometimes even if you can), learn to dodge. Dodging is useful even if you're not dual wielding. As an enemy attacks or recovers from an attack, sprint past them. Since most enemies are right handed, it's most effective to sprint to the right of them (their left). Go right past them and come back around. This can be especially useful for shepherding enemies into a smaller area (which Sweep can take advantage of). This battle tactic is especially useful for skirmishers and rogues, who usually find themselves lightly armed and armored (with, say, a pair of daggers or axes), but can be useful even for heavyset sword-and-board type guys. After practice, you'll get very good at predicting attacks from NPCs depending on their weapon style and even the likes of trolls and giants.
If you're dual wielding, dodging and shepherding is key, as you really don't have much to defend with. Successfully executed, you'll have your enemies in a tight bewildered circle or will at least have them from behind or another advantageous angle. The dual power attack can hit three or four enemies if you aim correctly. Sometimes dual wielding can be a bit fast (especially with two ranks of Dual Flurry), so heavier weapons may be preferred just so you can be more accurate in aiming your power attacks as you input them. Remember that the weapon in your left hand dictates the speed of this (and only this) attack, so an axe in the right and sword in the left or mace in the right and axe in the left are both good weapon combos.
Regardless of your melee style, axes are simply the best choice for crowd control. Damage over time from the bleeding perks means you can swing at an enemy and then pay attention to the next one. Also, the bleeding damage stacks, so two or three swings can send even a bigger enemy reeling. Dual axes with this perk can be devastating to crowds, as can the Sweep perk with a battleaxe (one of my favorite things to do). Often times, enemies will bleed to death while you're killing their comrades. Even if they don't, you've still dealt more damage to them without even having to hit them.
Finally, if you're the sneaky type, remember not just to invest in, but how to use, Shadow Warrior. Bash an enemy or dodge an attack, crouch, and tap (don't power attack!) as quickly as possible. If you don't manage a successful sneak attack this way or if you do and it still doesn't kill them, roll out of the way immediately! You'll have Silent Roll before you get Shadow Warrior, so don't worry. A successful sneak attack in the middle of open combat can outright kill an enemy, lowering the number of foes and therefore being efficient crowd control. It can even reposition you if you get a kill cam

For the record, I've had the most success--by far--by using Shadow Warrior on the side of an enemy rather than right in front. Even with 100 Sneak, an enemy may still see you if you're right in front of their face in the middle of combat. That, and it's much easier to dodge roll out of the way as soon as you're done attacking. Finally, remember that even if your sneak attack is unsuccessful, that dodge roll can still be useful, and you're already in a position to use it.
destruction spells that take up an area are nice, but if your trying to concentrate more on Mellee, try shouting.
but if your trying to concentrate more on Mellee, try shouting.
shouting.
shouting.
That's not melee xD