Okay, I want to make my character use two handed weapons, but wear light armor. Is this a bad idea, because I've never used 2 handed before.

You should be fine.

Two-handed weapons is all about offense with some defensive capability's(block).

Just put points into both health and stamina to make sure you can power attack and bash when needed and you will be fine.

Also carry some restore health and stamina potions with you as you will have both hands on your weapon making it hard to cast any restoration spells.

No, it is a barbarian build. It works great if you get used to it.