Yes - pretty much every game I tried from the market has worked on the Streak - which games are you finding don't work? Or are you just searching 'Dell Streak Games' ? You don't need to do that - just go to Market and search all the games. If a game has a free version try that first, if not you can get a refund within 24 hours if you don't like it/it doesn't work.
But yeah, i have about 30 odd games on my Dell Streak at moment (mainly free or lite) and all work great.
Robo Defense is AMAZING on the Streak - mate plays it on his Galaxy S, and has to scroll all the time to view play area, on streak you view it all at once!