Hey, I'm not a computer wiz so I have a really dumb question to ask. My sister gave me a DELL XPS t700r computer that had crashed on her. She lost the recovery backups to make matters worse.. I just played around with it a little and noticed every time I was going to try a installation it read that I couldn't because it was in DOS mode. My question is if I purchase a new operating system, would it be a breeze to install or would I need to do other things to get a operating system to install on this computer?