OK, I picked up Vista Ultimate (Upgrade) at Staples yesterday. I'm still confused/uncertain about some points and wonder if perhaps I should just return it (it's unopened). I checked at Microsoft's site and it says the new OS will install over my current XP Media Edition. I ran the Vista Upgrade Advisor and there are some issues. I have to uninstall my NeroVision program. I'm hopeing Ultimate comes with a CD/DVD burn program. Also, it appears I can't run my antivirus program, BitDefender, as is. I'm in touch with BitDefender with questions about a version that will work and how to upgrade to it. I guess Ultimate's program will protect me until I hear back from BitDefender. My HP PhotoSmart 7960 printer will not work with Ultimate and HP does not have a driver yet. I don't know how long it will be before I can use my HP printer, but, I do have another printer connected (Epson R2400) so it's not like I will be hurting there for awhile. The OS box says that both 32 and 64 bit DVDs are included, I have no idea which to run. And, should/could I do a fresh install instead of installing over my XP program? I have my Documents and Pictures saved on an external hard drive. I guess I should mention that I have 3 internal hard drives, 2 160GB drives that are currently set as RAID 0, and an 80GB hard drive that I use only as my scratch disc. I can and have, in the past, reinstalled my programs if a fresh install is best. I realize that there are a lot of questions here, but would appricaite any and all help. Thanks. Oh, one reason I was thinking about a clean install is because there is a Trojan that BitDefender can not remove in a file. It appeared using my old antivirus program, PC-Cillin.