I upgraded from win 98 to winXP home edtion. I have Direct X 8.1/ Pentium II 450 Mhz, 384 MB RAM. Everything works fine except playing back DVDs. I have sound and no video. Media Player 9.0 message says I do not have a decoder installed (I played DVDs just fine before the upgrade!) So it was suggested to get a player from Intervideo. Did that and during installation message said to uninstalled previously installed decoder. So I went forth and installed anyway. Still no video playback. Gatewat tells me the decoder isn't compatible with XP. Voodoofiles says its the graphics driver. I am currently using 3dfx Voodoo Banshee version 5.00.2462.0060 (banshee.dll) What are your thoughts? Is there a better driver? ???

You're missing a codec here i think,
personally i'm not aware of any free dvd codecs, but if you get a commercial one like powerdvd or windvd everything should work fine again.