is the Driver from GLSetup? because if so then its likely not to be a problem ... if not i'd get ahold of Glide2x and try again
there are alot of known bugs with Voodoo based cards and DirectX - they're just not 100% compatible because their drivers are just wrapped from Glide32 (Cut down OpenGL)
i'd suggest updating to WindowsXP as soon as, because that has very stable Voodoo Drivers
failing that, your can grab a GeForce2mx PCI for around £30-40 ... can even use it with the Voodoo2 if you like
Tsu'va Oni Ni Jyuuko Fiori Sei Tau!
One block follows the suit ... the whole suit of blocks is the path ... what have you found?