I bought a used laptop and the former owner partitioned the hardrive (no big deal) but added a second operating system on the other partition. I have windows 7 on the primary partiton but don't know how to uninstall an operating system and don't know if there is a risk of losing the files on the second partition. Is there a way for me to undo the partition itself? I probly won't anyway but I heard laptops don't function as well with partitions and might change my mind. Would I have to back-up my files externally if I did?