Copy over your preferences, and any obvious files that get created after installation (e.g. mailboxes in Eudora). Copy all your extra documents, etc, that you save from Word, Excel, etc, to your D: drive. Then you can format and clean install the OS. Then copy over your saved files. Just make sure you look thoroughly through your program files. I always use two partitions anyway.. one with the programs & OS, and one partition with the files I created.