DVD playing problems help!!

I am having DVD playing problems too. My machine is Win98se, PII 300mhz with a atapi DVD rom made by Raite model # RDR-108H. My video is a ATI Mach64 pci card with 8megs of video ram. My 3 hard drives are scsi hooked to adaptec 2940uw with 68pin hard drives. Also 250megs of RAM, so speed is not a problem. I can only play one of my DVD's and thats a older copy of The Net, which works fine. I have a copy of Swordfish and Gettysburg and neither will play. also I am using PowerDVD ver. 1.6 but does the same with a Acer hardware assit card and a Creative labs card too(Model# CT7160), both cards made to interface with the ATI card. I have had the same problem with a friends computer with a Athlon 800 mhz cpu and a sony dvd rom with powerdvd 2.0. whats the deal?

Thanks, look like I will get a DVD player and use the video option on my PowerMac 8600 to view the movies and replace the VCR thats there now.and now retire the PC and see if I can find it new home.

dude, it does not have to be that drastic, lol. find a friend with a stand-alone dvd player first. it really could be problems with the discs themselves. you will not know until you try them out first. [:)]

Try playing the DVDs in stand-alone DVD players. DVDs were meant to be played in dedicated hardware. Compatibility with DVD-ROM drives was a secondary consideration. If the discs don't work in stand-alone players, then the problem is with the discs themselves. If they play just fine in DVD players, then you've run into massive problems with computer hardware--for which there is little remedy other than to use new software/hardware/drivers.