You can do it either way. Personally I find it's a bit easier to just boot from the install DVD, since it's going to do that anyway, so you can just skip a step or two that way. The rest is really up to you. You will be given the option to format the drive during the install process, so if your current install is "all messed up" I would strongly recommend doing that. Upgrading over a damaged OS usually results in an even bigger mess than you started with. Whether or not you disconnect all the other drives is up to you.
My computer is all messed up so I bought a retail full version of Windows 7 Professional and I want todo a clean install.
I've never used a retail full version before, it has been an upgrade on a computer I purchased, or an OEM disc for computers I've built, and I'm a bit confused. On the computers I've built I had to format the hard drive first and then boot from OEM OS disc to install the OS and that's what I expected I would do with this retail full version of Win 7 Pro, but in the documentation, it tells me to start Windows normally, insert the Win 7 disc and I will be prompted to install Win 7 using one of two methods, upgrade from Vista, or choose custom if I'm running XP, or if I want to completely replace the current OS. Well I want to totally replace the OS because it has some problems, but does this mean that it will reformat the drive as part of the installation? I would like it to do that to insure that I have no flaky artifacts left from the old OS.
Also, during one of my reinstallation adventures several years ago, I accidently formatted the wrong drive and I wiped everything out. Since then, I've learned to unplug every drive but my C drive as a precaution, should I still do this, or since I'm running the set up from a booted OS, shouldn't it know which drive to install the OS on?
Any help would be greatly appreciated!
Thank you,
Ray

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