How to get rid of Antimalware Doctor and XP Antivirus?

I have these 2 rogue anit-spyware programs and I cant get rid of them. I ran a scan with MBAM but it keeps crashing in middle of the scan. I read a guide where it says to download root kill so i did that but my computer won't allow me to install it. So is there a way to get rid of these programs without having to download anything.