Downloaded a Trojan Virus and was detected and CPU shutted down and now Windows will not start

My wife accidently dowmloaded a Trojan Virus by trying to download a video. She says when dowmloaded my Anti-Virus program (Kaspersky 2009) detected it saying it was a Trojan Virus. Then Windows XP shutted down. She tried to restart but Windows would not run. She then used System Restored and restarted but Windows still would not start just a blank screen after Windows loading screen. I tried to go to safe mode but getting missing or corrupted Windows file. I then found a posting about if System Restore does not work to run in Safe Mode with command line and make a temp hive setting something at 0 then deleting the hive, which I did but Windows still would not start but would now run in Safe Mode. So I tried to run my Anti-Virus program but SCAN is not selectable and my license time remaining is UNKNOWN which I have 2 yrs left. Also my pictures in MY PICTURE folder are gone but found misc pictures in another folder. None of my programs I installed will run saying they are missing certain files. Is this because of the virus or because of System Restore? I was told my pictures would still be there if I restored but may need t reinstall some of my programs. I am being told by my works IT guy that it is the AV Virus 2009. Are there any suggestions to get my CPU working again & removing virus? Or getting my pictures back? I recently just had a baby and the pics are of her. I really want those pics back.

 

Desktop. HP Pavilion with Windows XP Media edition