Just a quick update, i've found a copy of mame that works on my xda, some of my roms work some dont

button mapping is proving to be a bit of a pain as the copy i've got is intended for a different pda ( dont know which, yet)
Anyhoo, i've got Donkey Kong Junior working ....ish and also Galxian and a few others, still early days but will let you know.