How ca i remove orion p virus from my pc in vista version?

i'm having 945 GCR desk top boad, SATTA, pentium duo, loaded vista ultimate pc. Few days back i frequently met one problem that is "one message will appear whenever i'm surfing the net that is " hosting disabled". Finally i came to know that was a "orion p" virus, now pleas help me to remove that virus from y pc.