You have win7 home premium according to what you posted.
Is your other profile an administrator or a standard user? (can you change things, install things etc?)
If your usable profile is an administrator, I'd rename the other one, and delete it, retaining the files. Then create a new administrator profile. Be aware, if this is due to a virus or malware, your machine will remain infected, open to attack by downloaders etc and you will get hit again.
If you can download under your current profile, grab a copy of mse (microsoft security essentials - its free) and a copy of malware bytes (again, free) install, update and run them.
Once you clean them off your machine - move all your documents, films, music whatever to an external hard drive, and reinstall your operating system and drivers, programs etc - you will still be at risk if you dont.
Wurz