out of date to play some of this newer mame stuff, it's a 1.1 ghz Duron with 128 megs of ram 
You are bound to find a performance upgrade on some games
w/ a better processor in the newer MAME version.
For example, I could never get Avengers in Galactic Storm
to play at all on my old 1.1 Ghz but when I upgraded to an
Athlon x2 last year it works great.
If you're money tight, another option is to not upgrade and
squeeze what you can out of that 1.1ghz, in which case MAME .129
may not be the best version for you...
One game I had to add to the post v .83 list ( was added around
v .90 or so)... The Crystal of Kings... love that one.