If you have a laptop primarily for gaming, I would get the highest resolution screen i can afford with at least a resolution of 1920x1080, with the performance that can back up 1920x1080 at native. If my budget doesn't permit that price/screen/performance matrix consider a more affordable laptop with a 1366x768 native screen.
But, if your laptop is for more than just gaming, I would get at least a 1920x1080 screen.
If the laptop can't handle the games at native then run your games at lower resolution. This has the effect of a bit of blur in the upscale to native, but you also don't sacrifice your productivity with non-gaming tasks.