I don't know if it's the Windows XP or not but when I tried Handy (Lynx emulator) the game seems to run about 2/3 speed compared to real Lynx. I have 1.4GHz P4 and 1GB RAM. Turning sound off or changing video setting didn't improve.

Compared to my old PPC 9600/200 (200MHz), 128MB RAM and Mac OS 8.6 Handy seems zippy on that Mac.