Check these in hijackthis, AND WITH ALL OTHER WINDOWS CLOSED, fix checked.

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = res://mshp.dll/sp.html#37049
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = res://mshp.dll/index.html#37049
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = res://mshp.dll/sp.html#37049
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = res://mshp.dll/index.html#37049
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Search_URL = res://mshp.dll/sp.html#37049
O2 - BHO: (no name) - {549B5CA7-4A86-11D7-A4DF-000874180BB3} - (no file)
O2 - BHO: ShowSearch module - {E2DDF680-9905-4dee-8C64-0A5DE7FE133C} - C:\WINDOWS\sysqw\mssearch.dll (file missing)
O2 - BHO: (no name) - {FD9BC004-8331-4457-B830-4759FF704C22} - C:\WINDOWS\sysqw\msiesh.dll (file missing)
O2 - BHO: (no name) - {FDD3B846-8D59-4ffb-8758-209B6AD74ACC} - (no file)
O2 - BHO: . - {587DBF2D-9145-4c9e-92C2-1F953DA73773} - C:\WINDOWS\sysqw\sysqw32.dll (file missing)
O4 - HKLM\..\Run: [Image] rundll32 C:\WINDOWS\image.dll,Install
O4 - HKCU\..\RunServices: [Image] rundll32 C:\WINDOWS\image.dll,Install

Then Reboot to safe mode (F8 on boot) and delete the following files/folders:-
NOTE: To avoid the risk of any of the above not being found due to them having the 'Hidden' attribute, first make sure that in Folder Options > View hidden and operating system files are set to show:
How to Show Hidden/System Files : http://www.xtra.co.nz/help/0,,4155-1916458,00.html

File > > C:\WINDOWS\image.dll

Then Reboot and post a fresh log for me to check.