Nothing works!!!! Need help!!!

I start any program, even my computer, it gives me a message saying "file not found." and a new message after that saying "no admin rights". This has never happened, but when thath happens a new program starts that i can see in Task Manager that says "Adobe Photoshop CS crack". The only things that work is Recyling Bin, Firefox and Task manager and the internet doesn't work properly. I can't give a hijackthis long because my hijackthis doesn't even open!! The pretty sure the virus came through P2P. I ran housecall and thats it. It found like 600+ viruses, but still didn't fix the problem.