Thanks for the information Win2kpatcher and schultzy. As you predicted it hasn't been easy to decrypt those files. So far I have figured out (and correct me if I'm wrong) that decryption would require a few things:
1. Set up a user account having the same user name and password as the original account. This may not be 100% necessary, but it seemed like a logical step.
2. Copy the user profile files from the original user directory under Documents and Settings to the new system. I do have these files, so that part's easy.
3. Duplicate the machine SID from the original windows installation. This took a little more time, but I successfully changed the machine SID of the new windows installation to look like the old one. Fortunately the old machine SID was recorded in the user profile directory, and free tools are available to make the task easier (it sure beats tweaking the registry by hand).
4. Change the user SID of the new account to be the same as the original one. This has proven to be a bit more difficult since (according to MS) there's no way to change the user SID of an account, and there's no way to specify a user SID when the account is created. I know the SID number I need, but it's lower than the numbers windows is generating, so I haven't figured this out yet.
So, step #4 is what I haven't figured out yet. My question is this: if I do succeed in changing the user SID back to the original one will this work? Will I be able to decrypt my files? Is there more to it than just copying the user key files and matching the machine SID, user SID, and user password?
I've also considered just replacing all five registry hive files with the old ones I recovered from the crashed drive. I'd probably have to do this from a recovery console since I doubt windows will allow me to overwrite active registry files, but it seems to me like it might work since the new OS was installed from the recovery disc of the old one. Once I decrypt the files I could just re-install the entire operating system to make the registry clean again.
Any ideas or opinions -- other than "don't EVER use MS encryption"?