I use n0p's port of DOSBox and it is very good, though lacks VGA support as he doesn't have a VGA device. I haven't had any problems with compatibility so far, apart from software that uses the dpmi DOS extenders (which tends to be just angband clones these days).
I tried n0p's recompilation of PocketSNES, however it does not seem to work on the x51v. You need to download the version that was made available in the PocketSNES thread in this forum (this should be better than the Morphgear one).