anybody know what dungeons repopulate so i can go and grind some skill levels?

I think they all repopulate after 30 in game days.

Although, if you want to grind some skills, this is an easier, if more boring way to do it. Aquire a summon flame atronoch spell. Use the spell to summon a flame atronoch, and hit it with your sword/bow to level up that skill. If you want to level up armor/block/resto, set the game to novice, find an enemy, let him hit you, heal, run back until magicka recharges, and let him hit you again, repeat until you are at the level you want. Also, if you want to grind smithing, iron daggers sell for more than it cost to make them. Buy the materials to make them, sell the daggers, wait 2 days, repeat

Not all of them repopulate. My favorite place to go is Arcwind Point(far west of Riften near the base of the Throat of the World) because there is a bunch of enemies and a dragon you can grind your skills on.

Most dungeons respawn 30 in-game days after you've cleared them (10 if you haven't). Places which do not respawn are listed here: http://www.uesp.net/wiki/Category:Skyrim-Places-Safe
So just grind away in any dngeons except for those you find in the link.

Well, I know the clearable ones repopulate every 30 daysl

Another way to grind combat skills is constantly attacking Shadowmere because she has such a fast health regen rate that it seems as if she has an infinite amount of health. (if you have her)

I'm pretty sure Helgan respawns.

True, it does. No idea why it's on the list :/

sweet, thanks for the notes.

No problem.

Forelhost, that is all.