U just install a good antivirus and run a scan. that will get rid of almost all viruses. U can also remove it from registry, but it won't go out of the hard disk. It just stops executing itself at the system startup.
to deleted the startup entry from registry
Code:
HKLM\software\microsoft\windows\currentversion\run
HKCU\software\microsoft\windows\currentversion\run
HKCU\software\microsoft\windows\currentversion\runonce
or else u can delete that by opening msconfig.

So, obviously the easiest way is to instal an antivirus.