iexplore.exe using 100% cpu

Hi,
Every now and then my system slows down to treacle, and when I check Task Manager find that iexplore.exe is using close to 100% cpu. Even when I close IE, the exe file continues to use almost all of the cpu. Just ran HijackThis - the log is shown below. I have no idea which of the 49 detected problems to fix - do any look like they'd be causing the iexplore.exe problem?

I use Avast AV software, and Windows firewall is on.
I have a number of Google applications - Gmail, Desktop and Toolbar.

Thanks if anyone can help!
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Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 6:22:21 PM, on 1/11/2007
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 SP2 (6.00.2900.2180)
Boot mode: Normal

Running processes:
C:\WINDOWS\System32\smss.exe
C:\WINDOWS\system32\winlogon.exe
C:\WINDOWS\system32\services.exe
C:\WINDOWS\system32\lsass.exe
C:\WINDOWS\system32\svchost.exe
C:\Program Files\Windows Defender\MsMpEng.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
C:\Program Files\Alwil Software\Avast4\ashServ.exe
C:\WINDOWS\Explorer.EXE
C:\WINDOWS\Mixer.exe
C:\Program Files\Picasa2\PicasaMediaDetector.exe
C:\Program Files\Google\Gmail Notifier\gnotify.exe
C:\Program Files\Common Files\Ulead Systems\DVD\USISrv.exe
C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
C:\Program Files\Windows Defender\MSASCui.exe
C:\Program Files\QuickTime\qttask.exe
C:\Program Files\Google\Google Desktop Search\GoogleDesktop.exe
C:\WINDOWS\system32\spoolsv.exe
C:\Program Files\Adobe\Photoshop Album Starter Edition\3.2\Apps\apdproxy.exe
C:\Program Files\Google\GoogleToolbarNotifier\GoogleToolbarNotifier.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Common Files\Ulead Systems\DVD\ULCDRSvr.exe
C:\Program Files\Google\Google Desktop Search\GoogleDesktop.exe
C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe
C:\Program Files\Alwil Software\Avast4\ashWebSv.exe
C:\Program Files\Internet Explorer\iexplore.exe
C:\WINDOWS\system32\taskmgr.exe
C:\Program Files\Microsoft Office\Office10\WINWORD.EXE
C:\Program Files\Internet Explorer\iexplore.exe
C:\Program Files\Spybot - Search & Destroy\TeaTimer.exe
C:\Documents and Settings\Michelle\Local Settings\Temporary Internet Files\Content.IE5\MX8FMH2D\HiJackThis_v2[1].exe
C:\Program Files\Trend Micro\HijackThis\HijackThis.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.theage.com.au/
O2 - BHO: Adobe PDF Reader Link Helper - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Common Files\Adobe\Acrobat\ActiveX\AcroIEHelper.dll
O2 - BHO: Spybot-S&D IE Protection - {53707962-6F74-2D53-2644-206D7942484F} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre1.5.0_07\bin\ssv.dll
O2 - BHO: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - c:\program files\google\googletoolbar4.dll
O2 - BHO: Google Toolbar Notifier BHO - {AF69DE43-7D58-4638-B6FA-CE66B5AD205D} - C:\Program Files\Google\GoogleToolbarNotifier\2.0.301.7164\swg.dll
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - c:\program files\google\googletoolbar4.dll
O4 - HKLM\..\Run: [PHIME2002ASync] C:\WINDOWS\system32\IME\TINTLGNT\TINTSETP.EXE /SYNC
O4 - HKLM\..\Run: [PHIME2002A] C:\WINDOWS\system32\IME\TINTLGNT\TINTSETP.EXE /IMEName
O4 - HKLM\..\Run: [C-Media Mixer] Mixer.exe /startup
O4 - HKLM\..\Run: [Picasa Media Detector] C:\Program Files\Picasa2\PicasaMediaDetector.exe
O4 - HKLM\..\Run: [{0228e555-4f9c-4e35-a3ec-b109a192b4c2}] C:\Program Files\Google\Gmail Notifier\gnotify.exe
O4 - HKLM\..\Run: [Ulead Quick-Drop] "C:\Program Files\Ulead Systems\Ulead DVD MovieFactory 4.0 Suite\Ulead Quick-Drop 1.0\Quick-Drop.exe" WINDOWCALL
O4 - HKLM\..\Run: [USIUDF_Eject_Monitor] C:\Program Files\Common Files\Ulead Systems\DVD\USISrv.exe
O4 - HKLM\..\Run: [NeroFilterCheck] C:\WINDOWS\system32\NeroCheck.exe
O4 - HKLM\..\Run: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKLM\..\Run: [Windows Defender] "C:\Program Files\Windows Defender\MSASCui.exe" -hide
O4 - HKLM\..\Run: [QuickTime Task] "C:\Program Files\QuickTime\qttask.exe" -atboottime
O4 - HKLM\..\Run: [Google Desktop Search] "C:\Program Files\Google\Google Desktop Search\GoogleDesktop.exe" /startup
O4 - HKLM\..\Run: [Adobe Photo Downloader] "C:\Program Files\Adobe\Photoshop Album Starter Edition\3.2\Apps\apdproxy.exe"
O4 - HKLM\..\Run: [Adobe Reader Speed Launcher] "C:\Program Files\Adobe\Reader 8.0\Reader\Reader_sl.exe"
O4 - HKCU\..\Run: [DeleteHistoryFree] C:\Program Files\DeleteHistoryFree\dhf.exe
O4 - HKCU\..\Run: [swg] C:\Program Files\Google\GoogleToolbarNotifier\GoogleToolbarNotifier.exe
O4 - HKCU\..\Run: [SpybotSD TeaTimer] C:\Program Files\Spybot - Search & Destroy\TeaTimer.exe
O4 - HKUS\S-1-5-19\..\Run: [CTFMON.EXE] C:\WINDOWS\System32\CTFMON.EXE (User 'LOCAL SERVICE')
O4 - HKUS\S-1-5-20\..\Run: [CTFMON.EXE] C:\WINDOWS\System32\CTFMON.EXE (User 'NETWORK SERVICE')
O4 - HKUS\S-1-5-18\..\Run: [CTFMON.EXE] C:\WINDOWS\System32\CTFMON.EXE (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\Run: [CTFMON.EXE] C:\WINDOWS\System32\CTFMON.EXE (User 'Default user')
O4 - Global Startup: Microsoft Office.lnk = C:\Program Files\Microsoft Office\Office10\OSA.EXE
O8 - Extra context menu item: E&xport to Microsoft Excel - res://C:\PROGRA~1\MICROS~2\Office10\EXCEL.EXE/3000
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.5.0_07\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Sun Java Console - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.5.0_07\bin\ssv.dll
O9 - Extra button: (no name) - {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O9 - Extra 'Tools' menuitem: Spybot - Search & Destroy Configuration - {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
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
O16 - DPF: {05CA9FB0-3E3E-4B36-BF41-0E3A5CAA8CD8} (Office Genuine Advantage Validation Tool) - http://go.microsoft.com/fwlink/?linkid=58813
O16 - DPF: {0E8D0700-75DF-11D3-8B4A-0008C7450C4A} (DjVuCtl Class) - http://www.lizardtech.com/download/files/win/djvuplugin/en_US/DjVuControl_en_US.cab
O16 - DPF: {11260943-421B-11D0-8EAC-0000C07D88CF} (iPIX ActiveX Control) - http://www.ipix.com/download/ipixx.cab
O16 - DPF: {CF40ACC5-E1BB-4AFF-AC72-04C2F616BCA7} (get_atlcom Class) - http://www.adobe.com/products/acrobat/nos/gp.cab
O16 - DPF: {E7DBFB6C-113A-47CF-B278-F5C6AF4DE1BD} - http://download.abacast.com/download/files/abasetup162.cab
O20 - AppInit_DLLs: C:\PROGRA~1\Google\GOOGLE~2\GOEC62~1.DLL
O23 - Service: avast! iAVS4 Control Service (aswUpdSv) - ALWIL Software - C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
O23 - Service: avast! Antivirus - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashServ.exe
O23 - Service: avast! Mail Scanner - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe
O23 - Service: avast! Web Scanner - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashWebSv.exe
O23 - Service: GoogleDesktopManager - Google - C:\Program Files\Google\Google Desktop Search\GoogleDesktop.exe
O23 - Service: Google Updater Service (gusvc) - Google - C:\Program Files\Google\Common\Google Updater\GoogleUpdaterService.exe
O23 - Service: Ulead Burning Helper (UleadBurningHelper) - Ulead Systems, Inc. - C:\Program Files\Common Files\Ulead Systems\DVD\ULCDRSvr.exe

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