So an update, the emulator is snes9x2002. I tried with 2005 and 2010, both of which performed significantly worse.

What is the best emulator for a Pi B with 256mb. I assume it's snes9x2002 ? If that won't run StarWing then I assume nothing will. Regardless, what's the best for just standard Mario games etc. I tried both and 2010 and 2002 work fine with those simple sprite games.