1) install Win7 easy transfer on your vista box (http://windows.microsoft.com/en-US/w...-easy-transfer)
2) Use WET to backup everything
3) Copy your important docs, downloaded software app installers, WoW folder, etc. to a separate backup drive*
4) Install Win7 on the new RAID
5) Install all the same apps on Win7
6) Run WET on Win7 and restore what you backed up in step 2.

Note that there are some issues with WET getting everything. http://www.extremetech.com/article2/...2348168,00.asp

Hope that helps.

* I would also backup your c:\users\<yourusername>\ folder in its entirety just in case.