you have to install the DVD portion of your video drivers first before you install all the other drivers. they should be on your video card's driver CD.
Okay, to make a long story short, I recently had to format my hard drive and reinstall Windows and all that. (Almost) everything has been working perfectly, but this DVD-ROM is driving me crazy. I had rarely ever used my DVD-ROM to play DVDs, but I know that it did. It plays audio discs perfectly and can explore data discs as smoothly as normal. But when it comes to DVDs, it gives me the error that it can't read the drive. I went on the Hitachi website, and they said that the problem wasn't the hardware, but that it was I didn't have a DVD decoder and something about MPEG2. They told me to get InterVideo WinDVD since it came with the DVD decoders, and so I did. Even after two or three restarts, it still wouldn't read my DVDs. Someone else suggested PowerDVD. I got that, and still no luck.
I have Gateway Essential Desktop from 1999-ish, Pentium III processor, Windows 98SE, DirectX 8, and a Hitachi GD-5000 DVD-ROM. If you need any other information, just reply. Thank you for your time.