I'm a fairly experienced GM and I'm looking to start a fresh campaign in D&D, probably 3.5, probably forgotten realms - but we can discuss that!
I have a very relaxed style and I'm seldom dogmatic about rules; I like to experiment with unusual custom/house rules and strange scenarios. I also like to build story-driven campaigns around player choice, ethical quandaries, and character development. This probably won't be for you if you're worried about detailed character placement during battles and measuring the area of effect to the last centimetre.
So the bottom line would be to aim to have fun with it.