However, I believe you can do easy transfer to back up data and settings, to save you from reconfiguring your apps again.
Hmm.
Interesting ,
can you or anyone else talk a little bit about this point and how to achieve it ..
pls , even in tiny steeps 
thanks again
What I have done is move all my files and folders to the desktop prior to the upgrade, Then do the New clean upgrade, then look for windows.old in the C: directory tree and find you files and folders where you put them before the upgrade usually users-your_user_name-desktop, now move them where you want them to be and reinstall your applications. I also export all favorites, bookmarks, contacts, and emails before the upgrade and place them on the desktop. I haven't had any luck getting my pictures,music, etc back after the upgrade if they are left in the "My Music, My Pictures, My Documents, etc" which is why I recommend moving them to the desktop and not using the system default folders. Best of luck, I have been much happier on x64 and I have found all the drivers required to run my peripherals.