I'm afraid it is very unlikely this is a virus issue. The same thing just happened to my sys. (U gots an Intel "Pheonix" Bios chipset by any chance?)
Check it out mang:
What is going down is, as you guested, a registry problem. Don't try to fix it with regedit, you - Will - go insane. (I almost did myself.)
If your video is behaving more like its very choopy; as in jumping forward to keep sync with the audio, chances are 99% this is your answer. Prob. is anyways.
First: Don't boot into 'Last Known Good'. It mangles things worse.
What To Do Then:
Uninistall all audio drivers & non M$ OEM codecs (including player softs like the creative trash - I gots a CL. Audigy and hate that app). Now uninstall every non-oem vid codec. This means all ur software DVD playes too.
DONT uninstall your actual graphics drivers!
From M$, Download the "DirectX 9.0c Redistributable" (Its For sysadmins, search the site.) Now, Install it (HRESULT=overwrite everything). Re-install any DvD players and all mpeg-2 tools. Next, D/L the "Gordian Knot Codec Pack" from
http://sourceforge.net (not the 'rip' pack). Install this beast, (skip the lame player. - ))`Don't,(( - installl ffdshow; it's unstable when things are flakey already.
Relax, you are A_lmos-t done. You should now have an app installed called the "G-spot Codec Appliance". (If it wasn't in Gordian Knot; get K-Lite codec pack. Fuzzy mem.) G-spot has a feature to scan your system for misconfigured codecs, but you should have few, if any, misconf. at this point. Now is the time to re-install your audio drivers, sans the Creative Media Center (Its Bad I tell You!).
Final advices: if you use Nero Showtime, OR NVDVD, make sure to set them to use their own internal audio routines, instead of an external AAC decoder. Also, I suggest trying "The Core Media Player" for non-dvd movies; it provides exponentially more control and tweaking possibilities than the Creative Labs Bloatware Centre. (i.e., changing the default DirectShow renderer on the fly && individual configs of many codecs from within the player itself.,etc.)
Sorry for much verbs; been awake all night. Someone in the forum PLEASE let me know if I'm F.O.S in this post. And if it helped of course... peace and anarchism kids - and throw in some Lllove; like Barry White was jiven at ya.