I wish to format my hard drive because I am going to upgrade. However, my computer came with windows pre-installed and I was given a windows disk. I don't think it is a recovery disk because when I run it, it gives me the option to install windows. I have the product activation key, but will windows accept after I have formatted as I already used it? Can I install windows at all? Sorry to ask such noobish questions, but at least I will know for future!!