In my opinion you cant go past Brunni's MMSPlus.
Great emulation, beautiful GUI with loads of options, even crops the blank bar down the LHS of the screen a lot of games had even on the original hardware (Most old tvs dont display the outermost pixels of the image).
PSPMaster is also very popular and a quality emu, guess its personal preference.
EDIT: If a mod reads this could you update MMSPlus's front page menu bar links (MS and GG) to the latest versions release thread (linked above), theyre out of date. Cheers.
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