I've got a slight scratch on my ipod touch screen (and I didn't throw it down the stairs or anything silly). I went for the clear film screen protector and a silicon case from the apple store, it works really well for me, the film over the screen actually has nicer (smoother) feel than the screen for touch control I reckon and you never notice it's there because the edges are covered by the silicon case. It doesn't make it too bulky, only downside is I can plug in my headphone as the hole in the case is too small, you could just cut it slightly bigger but I got a extension like they sell for the iphone headphone socket, does the job lovely...
