bill,
Win7 uses a different file layout for the user folder directories. To transfer your user logon ids, settings, mailboxes, address book, favorites etc I recommend
windows 7 easy transfer. Be sure to download the appropriate file for the OS you are migrating from: XP or Vista, and 32-bit or 64-bit. (Please be aware of a potential issue with easy transfer if your XP/Vista was not on your C: drive: there are reports of boot problems because the new W7 OS is on C: and it is trying to reference the old drive letter.)
You should also decide if you are installing Win7 32-bit or 64-bit. If your computer can support it I suggest the 64 but note that the 64-bit cannot run the very old 16-bit programs without virtual emulation. The biggest advantage of 64-bit is that it can reference RAM memory beyond 3.25GB.
Also, if you are migrating from XP it means a completely new install but the truth is, even if you are upgrading from Vista, a clean install is still more stable. Of course the disadvantage to the clean install is that you must reinstall all your applications as well.
It is also a good idea to download the W7 drivers for your computer to a CD or USB flash drive, in your chosen 32 or 64-bit, prior to install, especially the drivers for your motherboard: network etc. Once you can see your hardware and get network connectivity, W7 can get to the internet to download the rest of the drivers.
Good luck.