Ciao....Hai un bel casino sul pc...
Io SE fossi in te (quindi decidi tu se fidarti XD) fixerei un pò di cose:
C:\Windows\xpupdate.exe
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,SearchAssistant = http://search.bearshare.com/sidebar.html?src=ssb
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = http://search.bearshare.com/sidebar.html?src=ssb
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = http://search.bearshare.com/sidebar.html?src=ssb
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,SearchAssistant = http://search.bearshare.com/sidebar.html?src=ssb
O3 - Toolbar: My Global Search Bar - {37B85A29-692B-4205-9CAD-2626E4993404} - C:\Programmi\MyGlobalSearch\bar\1.bin\MGSBAR.DLL
O4 - HKCU\..\Run: [Windows update loader] C:\Windows\xpupdate.exe
O20 - AppInit_DLLs: c:\windows\system32\ldcore.dll

Poi altre voci, di cui però non sono sicuro.