A browser going to the wrong homepage is
browser hijacking rather than a virus. This
previous thread relates to it too. Mentioned there and in the links in the posts in this thread is
CWShredder. This seems to be the most popular tool to use to get rid of the pest.
A program called
HijackThis is good for analysing the files and Registry entries that are causing the hijacking. Some computer knowledge is needed to make sense of it and act on the information though.
Also installing
RegistryProt should stop your browser being hijacked again.
Note: Clicking on the links above for CWShredder and HijackThis will start the downloads. Whilst these utilities are designed to be good for your computer, I think it would be best to read via Google what users have to say before running them.