I just got around to download the NXE update, and while experimenting I stumbled upon another cool feature I've been missing for a while!
You can actually delete games in which you have 0 achievements and gamerscore from your games played list. I used to have a lot of these myself, but now I have none!
All you need to do is to go into Xbox Guide, go to the Games section, select Achievements, scroll down to a game with 0 achievements and gamerscore, and hit X to trigger Delete Game History. Easy, huh?