I will leave others to suggest how to dual boot with, I assume 2 drives, master and slave. I ran a dual boot of XP and W7 64 bit using 3 partitions, 50 gig each for XP and W7 and "My Documents" common to both. The only problem I encountered were:1. The W7 would only allow 3 out of 4 Gig RAM to be used( There is, I believe, a reg edit for this) and 2. Restore points in W7 were wiped when XP was launched. Again I think this can be sorted if you look in Google. Havin run for 2 - 3 weeks I am now on W7 and able to use full 4 Gig RAM. I had to buy new version of Acronis True Image (version 2010) for W7.