Bueno, parece que ya anda bien! Muchisimas gracias!
Aquí dejo el log:

Logfile of HijackThis v1.99.1
Scan saved at 11:53:02 PM, on 7/25/2006
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 SP2 (6.00.2900.2180)

Running processes:
C:\WINXP\System32\smss.exe
C:\WINXP\system32\winlogon.exe
C:\WINXP\system32\services.exe
C:\WINXP\system32\lsass.exe
C:\WINXP\system32\svchost.exe
C:\WINXP\System32\svchost.exe
C:\WINXP\system32\spoolsv.exe
C:\WINXP\system32\nvsvc32.exe
C:\Program Files\Prevx1\PXAgent.exe
C:\WINXP\system32\WgaTray.exe
C:\WINXP\Explorer.EXE
C:\Program Files\VIA\RAID\raid_tool.exe
C:\Program Files\Analog Devices\Core\smax4pnp.exe
C:\WINXP\system32\RUNDLL32.EXE
C:\Program Files\Java\jre1.5.0_06\bin\jusched.exe
C:\WINXP\system32\ctfmon.exe
C:\Program Files\Messenger\msmsgs.exe
C:\Program Files\Google\Web Accelerator\GoogleWebAccWarden.exe
C:\Program Files\Google\Web Accelerator\googlewebaccclient.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\Program Files\MSN Messenger\msnmsgr.exe
C:\WINXP\system32\svchost.exe
C:\Program Files\HJT\HijackThis.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Local Page =
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Local Page =
R1 - HKCU\Software\Microsoft\Windows\CurrentVersion\Int ernet Settings,AutoConfigURL = http://localhost:9100/proxy.pac
O2 - BHO: AcroIEHlprObj Class - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Adobe\Acrobat

5.0\Reader\ActiveX\AcroIEHelper.ocx
O2 - BHO: Google Web Accelerator Helper - {69A87B7D-DE56-4136-9655-716BA50C19C7} - C:\Program Files\Google\Web

Accelerator\GoogleWebAccToolbar.dll
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre1.5.0_06\bin\ssv.dll
O2 - BHO: Windows Live Sign-in Helper - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Program Files\Common

Files\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O2 - BHO: IeCatch2 Class - {A5366673-E8CA-11D3-9CD9-0090271D075B} - C:\PROGRA~2\FLASHGET\jccatch.dll
O3 - Toolbar: FlashGet Bar - {E0E899AB-F487-11D5-8D29-0050BA6940E3} - C:\PROGRA~2\FLASHGET\fgiebar.dll
O3 - Toolbar: Google Web Accelerator - {DB87BFA2-A2E3-451E-8E5A-C89982D87CBF} - C:\Program Files\Google\Web

Accelerator\GoogleWebAccToolbar.dll
O4 - HKLM\..\Run: [High Definition Audio Property Page Shortcut] HDAShCut.exe
O4 - HKLM\..\Run: [RaidTool] C:\Program Files\VIA\RAID\raid_tool.exe
O4 - HKLM\..\Run: [SoundMAXPnP] C:\Program Files\Analog Devices\Core\smax4pnp.exe
O4 - HKLM\..\Run: [SoundMAX] "C:\Program Files\Analog Devices\SoundMAX\Smax4.exe" /tray
O4 - HKLM\..\Run: [DAEMON Tools-1033] "C:\Program Files\D-Tools\daemon.exe" -lang 1033
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\WINXP\system32\NvCpl.dll,NvStartup
O4 - HKLM\..\Run: [nwiz] nwiz.exe /install
O4 - HKLM\..\Run: [NvMediaCenter] RUNDLL32.EXE C:\WINXP\system32\NvMcTray.dll,NvTaskbarInit
O4 - HKLM\..\Run: [SunJavaUpdateSched] C:\Program Files\Java\jre1.5.0_06\bin\jusched.exe
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINXP\system32\ctfmon.exe
O4 - HKCU\..\Run: [MSMSGS] "C:\Program Files\Messenger\msmsgs.exe" /background
O4 - Startup: Adobe Gamma.lnk = C:\Program Files\Common Files\Adobe\Calibration\Adobe Gamma Loader.exe
O4 - Global Startup: Microsoft Office.lnk = C:\Program Files\Microsoft Office\Office\OSA9.EXE
O4 - Global Startup: Run Google Web Accelerator.lnk = C:\Program Files\Google\Web Accelerator\GoogleWebAccWarden.exe
O4 - Global Startup: AutoCAD Startup Accelerator.lnk = C:\Program Files\Common Files\Autodesk Shared\acstart16.exe
O8 - Extra context menu item: Download All by FlashGet - C:\Program Files\FlashGet\jc_all.htm
O8 - Extra context menu item: Download using FlashGet - C:\Program Files\FlashGet\jc_link.htm
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.5.0_06\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Sun Java Console - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.5.0_06\bin\ssv.dll
O9 - Extra button: FlashGet - {D6E814A0-E0C5-11d4-8D29-0050BA6940E3} - C:\PROGRA~2\FLASHGET\flashget.exe
O9 - Extra 'Tools' menuitem: &FlashGet - {D6E814A0-E0C5-11d4-8D29-0050BA6940E3} - C:\PROGRA~2\FLASHGET\flashget.exe
O9 - Extra button: Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Program Files\Messenger\msmsgs.exe
O9 - Extra 'Tools' menuitem: Windows Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Program Files\Messenger\msmsgs.exe
O12 - Plugin for .mp3: C:\Program Files\Internet Explorer\PLUGINS\npqtplugin3.dll
O16 - DPF: {0EB0E74A-2A76-4AB3-A7FB-9BD8C29F7F75} (CKAVWebScan Object) - http://www.kaspersky.com/kos/eng/partner/default/kavwebscan_unicode.cab
O16 - DPF: {6E32070A-766D-4EE6-879C-DC1FA91D2FC3} (MUWebControl Class) - http://update.microsoft.com/microsoftupdate/v6/V5Controls/en/x86/client/muweb_site.cab?1153503945718
O18 - Protocol: livecall - {828030A1-22C1-4009-854F-8E305202313F} - C:\PROGRA~2\MSNMES~1\MSGRAP~1.DLL
O18 - Protocol: msnim - {828030A1-22C1-4009-854F-8E305202313F} - C:\PROGRA~2\MSNMES~1\MSGRAP~1.DLL
O20 - Winlogon Notify: WgaLogon - C:\WINXP\SYSTEM32\WgaLogon.dll
O23 - Service: Adobe LM Service - Adobe Systems - C:\Program Files\Common Files\Adobe Systems Shared\Service\Adobelmsvc.exe
O23 - Service: Autodesk Licensing Service - Autodesk - C:\Program Files\Common Files\Autodesk Shared\Service\AdskScSrv.exe
O23 - Service: NVIDIA Display Driver Service (NVSvc) - NVIDIA Corporation - C:\WINXP\system32\nvsvc32.exe
O23 - Service: Prevx Agent (PREVXAgent) - Unknown owner - C:\Program Files\Prevx1\PXAgent.exe" -f (file missing)