lameboy issue

Hello everyone here's my issue with the GB/GBC emulator for DS, Lameboy:
when I load gb/gbc roms that are 4mb I get problem with the gameplay screen: freeze sometimes, problems in colours and well displaying of the game. It also completely freezes when i try to load saves from the load state option. There aren't many features in the emulator that allows us to settle a good configuration for games, so my questions are:
-How to trim a gb/gbc game, it might fix the size problem and correctly load the rom, but i can't find a gb/gbc rom trimmer :(
-Is there any powerful Gb/Gbc emulator for ds than lameboy?Nintendo DSi with R4iGold (www.r4i-gold.com)
Please help!
Gbc nostalgic 8)

That is lameboy...
I get also with some 4mb roms issues. Lameboy isn't perfect you know

No gbc rom trimmer?
No powerful emulator?
No fixes for slow speed game?
:-\ :(