Hi ferrariman:
I'm glad that you've discovered GE and that you have decided to join the forum. I think that you will find the GE community to be welcoming, friendly. and informative. I hope that you will decide to buy GE and stay for a while.
As far as your questions go, I think that you can create any sort of
2D game with GE. GE compiles to WinAll,Pocket PC, and Linux platforms, but Makslane (GE's amazing creator) tells us that he plans to support compilation to more platforms in the future.
Creating games is easy(once you learn the program). For many games, there is very little scripting. If you have a working knowledge of C programming, the sky is the limit and a good C programmer could probably create programs well beyond the scope of what is advertised. Most games, though, don't need anything more than what is already built into GE. Many games can be built almost without scripting. I'm still learning things everyday about GE and I've been using it for quite a while now.
One word of caution though, GE is like any complex program. It takes a little time to get to know what the program can achieve and how to achieve it. If you have the fortitude to stick with it, I don't think you will be disappointed. GE can become quite addictive.. It is a great neuro transmitter stimulant and it definitely increases seretonin levels when you accomplish something new!
I'll leave your question on sprite editors to someone else. ..