I would suspect the upgrade from 98 to XP then.
If the intro splash screen is being played upside down then you have a
severe problem with DirectPlay. That is the system used to play sounds, and show video (or a still picture, as the intro is), and DirectPlay dates from way before DirectX 8.
You may well find problems with other DirectPlay programmes(like video utilities).
Or maybe some third-party application which installed non-standard DirectPlay CODECS has been installed. We had this problem with someone in MBT, and the only way to fix it is to remove the faulty CODECS and revert to Microsoft default.
[edit - this is the MBT forum - I got confused!
]
Try the following thread
link for details on sound problems, and codecs. The option to convert your sound files from MP3 as issued, to WAV should be adressed in there too (but with upside down splash screens, you are possibly completely messed with your DirectPlay files in the "upgrade" is my guess
)
I take it you have visited
www.windowsupdate.com and upgraded xp?.
Have you also visited the manufacturer's site for your sound and video cards (and any other peripherals, like CD drive, modem etc) and upgraded the drivers to the latest XP models?
Personaly - I just buy a new PC these days if I need the latest M$ operating system. I
did try a windows 95 upgrade of a Windows 3 system once, and that was a total disaster. I installed a new disk drive and installed a full 95 install (not upgrade version!) onto the virgin drive in the end, and then converted the jumpers on the old drive and installed that as a slave D: drive and read the data files I needed from there. Once that was done, I formatted it and used it as a data drive. After that experience - new OS=new PC, for me.
Cheers
Andy