I would say picking Adsense or YPN is a tough choice. You have to give weight to the strict Adsense policies and guidelines that can halt your participation without notice. On the other hand Yahoo is smaller and their interface is somewhat confusing, so much so that you could easily spend a couple of hundred dollars more than you wanted to if you don't pay attention to your account settings. Personally I was not impressed with YPN and thought they were behind a major player like Adsense. So I would recommend Adsense, but only if you are comfortable with the constant changes and updates Google has been making to their advertising rules. Edit: I just saw the OP was banned. Hope it wasn't because of this thread!
The problem with YPN is getting accepted into the network. Adsense is much easier to get accepted but don't try to game the system or you'll be banned for life.
adsense rocks the $100 minimum sucks for the new site though. Last time I messed with yahoo it was $50 minimum, but it takes forever too. I think adsense looks better, is faster, more customizable and serves up more relevant ads in my opinion anyway. Never hurts to explore all options though.