when i purchased my computer, circuit city apparently partitioned my hard drive. my HD, was 350 gigs, but they took a 9 gig piece, an placed my recovery stuff on it, instead of giving me a recovery or win vista disk. my main disk is designated C:. the partition is D:. i need to format my C:, but can't, because it says drive is in use. how do i boot up into D:, so that i can format my C:, and then move my recovery stuff from D: to C: