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#21
As another suggestion, since you are so unsure about this process...I'd take a step back and re-examine. You may just need some assistance in getting the programs for reinstallation and your data backed up. I really am starting to think a dual boot isn't going to do what you want. This would be a good time to seek out a friend who's well versed in computers and can sit down in front of your computer to take a look. Aside from "illegal/warez" apps, you should be able to obtain the discs or files needed for your apps.
Either way, setting up a dual boot, while being an old, stale technology, is easy to do, if you pick the wrong partition or make a mistake, you could render the system unbootable. You would want to have a good backup of your data before trying this anyway...just in case.
No matter what, the solution seems to go back to getting a method of backing up your data, getting the apps ready, and just doing the clean install. And, as Arc said, a backup drive will cost far less than a second license for Windows 7.