I use neoragex (nrx) occasionally (well I use most arcade emulators from time to time), and I had no trouble running it on XP after selecting the proper settings.
The legal versions ended at 0.6b (released in 1999), and they could play both MGD2 and decrypted sets. The hacked versions cannot play MGD2 sets; in fact nrx will close down if it detects a MGD2 set, no doubt a side-effect of the hacking.
The things I like about nrx is that it's fast; and it can autodetect new sets even if they're not on the list. For example even though Pochi and Nyaa is a 2003 game, it gets detected and runs perfectly on 0.6b - as long as you use the decrypted set.
The bad thing is mentioned above, the fact that the encrypted sets cannot be used - they need to be decrypted first.
My favourite version would be 4.8 as it runs just about anything.