Computer Buggered!! program.exe is not a valid win32 application

[inferlogic]

Hi experts,
I have a serious problem with my friends computer, so bad in fact that I cannot run hijack this without getting the error hijackthis.exe is not a valid win32 application, even my search engines are hikacked so I can't search for any help or answers. Can someone help to at least get hijack this running.

Thanks