what really bothers me is that.. some SNES roms that can be played on the PSP, tend to lag... and they're only like, 2d!... while, the PSP games don't lag and they're 8123281 times better (gfx wise) then the SNES roms...
can someone tell me why it's like that??
That's what happens with emulation... alot of the processing power is spent just emulating the system. With SNESTYL, it actually makes use of the PSP's GPU which makes things faster, unless you're dealing with a more advanced and complicated graphics system (like with StarFox and Mario Kart).
Emulating takes a lot of horsepower. The more recent the system, the more problematic it is to emulate. Tweaking the emulator settings for games when required gets good results for the most part.
What were you expecting? Homebrew that runs as smooth and looks as good as a UMD game??? Try making the speed 333- it might help. SNES emulation is probably the best stuff around on the PSP.