Virus/Trojan Problem, Chrome hijacked

Hello, thank you for reading my problem. Here it is:

Running XP home, SP3. Intel core 2 duo 3GHz, 2gig ram. Using chrome and IE8. AVG free for antivirus, Windows firewall active. Computer experience: Novice.

The symptoms are: homepages are hijacked by "searchnu.com/414" in IE8, can't open a second tab and in Chrome (my main browser) the homepage works (google), but in any new tab, the web address bar is blank and when I type in a search, it goes through "search-results.com". Also random sound clips appear without any place to stop them other than closing the browser. Haven't noticed any else yet but I want to fix this before it gets worse.

What I have done so far in order: ran malwarebytes, spybot SD, full virus scan with AVG free (all fully updated and run several times)

Result:
malwarebytes found this:

Files Detected: 2
C:\Documents and Settings\Owner\My Documents\Downloads\mplayer_Setup (1).exe (PUP.Bundle.Installer.OI) -> Quarantined and deleted successfully.
C:\Documents and Settings\Owner\My Documents\Downloads\mplayer_Setup.exe (PUP.Bundle.Installer.OI) -> Quarantined and deleted successfully.

(end)

spybot nothing (other than cookies)

AVG nothing

Thank You in advance for your help.