it's been around for a while... most Anti Virus's will get rid of it - HOWEVER if you're using XP - turn 'System Restore' off otherwise it'll be back....
which mydoom is it theres quiet a few variants of it such as: mydoom-a mydoom-y go here and download the standalone disinfector run it, and do all the windows update. that should get rid of it. depending on what variant it is http://www.sophos.com/support/disinfection/mydooma.html
