Very Slow and often freezing PC (Vista)

[floparis12]

Hello,
I have a quite modern and powerful computer since Octobre 2008.
It runs under Windows Vista.
All was good until around 10 days ago : since then the computer is slow and it freezes from time to time (especially with Live Messenger), with no other solution than to shut the computer down manually and restart it.
Do you see any problem on this computer ?
What should I do ?

Thank you !!!

[drongo]

Please download in my signature special avz, put it in new folder on desktop.
Please execute this script in avz http://virusinfo.info/showthread.php?t=9207)
(Do remember before execution scripts to exit antivirus and disconnect from internet, disable System Restore )

begin
SearchRootkit(true, true);
SetAVZGuardStatus(True);
 QuarantineFile('C:\Program Files\Softex\OmniPass\SCUREDLL.dll','');
 QuarantineFile('N:\autorun.inf','');
 QuarantineFile('M:\autorun.inf','');
 QuarantineFile('c:\program files\softex\omnipass\opvapp.exe','');
 TerminateProcessByName('c:\windows\cdctr.exe');
 QuarantineFile('c:\windows\cdctr.exe','');
 DeleteFile('c:\windows\cdctr.exe');
 DeleteFile('M:\autorun.inf');
 DeleteFile('N:\autorun.inf');
BC_ImportAll;
ExecuteSysClean;
BC_Activate;
ExecuteRepair(6);
ExecuteRepair(8);
ExecuteRepair(9);
RebootWindows(true);
end.

Please upload the quarantine according to appendix 3 of rules (http://virusinfo.info/showthread.php?t=9184) , by link http://virusinfo.info/upload_virus_eng.php?tid=40095
After that make a set of logs according to rules: http://virusinfo.info/showthread.php?t=9184