Perhaps the best thing to do is to wipe and reinstall Windows. I don't envy you. Then take your time and plan the purchase of your Mac. I prepared for the switch by installing syncback (freeware version) and letting it back up "my documents" to a NAS drive every night at 1am. When I got my Macbook, I simply turned off my old Dell Laptop, turned on my Mac, connected to the NAS drive and brought over all my stuff in a matter of minutes. Of course that doesn't include applications. It took me some time to come to the conclusion that iWork and OpenOffice.Org/LibreOffice were good enough so I could avoid putting MS Office on my Mac. Other apps took a while as well. But I had all my documents, music, movies, etc on my Mac minutes after bringing it home and I didn't need Apple's service to transfer my stuff from my PC to my Mac.
Another thing I did was I bought 1 to 1. I then would go to the Apple store empty handed and use one of their machines to log in to my .me account and use "back to my mac" to use my machine as if I was at home. That way all my network drives showed up. They helped me through setting up iPhoto and using iWeb, both of which I later slowed down or stopped using altogether. Still, it was nice to use my 1 to 1 sessions to "do real work" rather than have them walk me through some canned example.
So for the "need" part of your situation, bite the bullet and reinstall Windows. This should buy you 6 months to a year to "plan" your switch to Mac. Next, get a decent NAS drive and back your stuff up to it manually or using software like syncback. Last, when you get your Mac you will be able to plug it in and transfer your files over in minutes from your NAS drive. Of course if you plan this right, you could time your purchase to coincide with Apple's next Macbook Pro refresh. I doubt you will want to wait an entire year for Apple's (expected) next Macbook Air refresh.