Theme Suggestions

Hi,
I’m using WP 2.3 and I’m searching for a theme. I have a few questions:
1. Does my theme need to be chosen from the 2.3 compatible themes listed in the codex?
2. New to this, so I think it should be widget ready. Is this true?
3. I want to put adsense in it, so should I choose one that’s adsense optimized?
4. Are some themes easier for a newbie to work with than others?
Any have any suggestions?
Thanks