FIRST STEP: Do not connect SSD, go into bios and check if HDD is set to IDE or AHCI.
.. If AHCI, your good to go.
.. If IDE, then correct, it. DO NOT change Yet.
Apply the followinf "fix" first. You can select either "let MS fix it, or fix it yourself method. Once the registry is fixed, shut down (or reboot) and go into BIOS and change to AHCI
.. Why - You need ahci mode for windows to pass the TRIM command to SSD.http://support.microsoft.com/kb/922976
Now for the SSD.
.. Disconnect HDD. (if you do NOT windows will use the system partition on the HDD).
.. Connect SSD
.. Install windows just as you would to a HDD.
with a 60 GIG SSD, you ONLY have about 50 gigs of usable space, so YOU must monitor used/free space. You Do NOT want to go over 90 % used!!
Apply thes tweeks to save space.
.. 1. Disable Hibernation, saves an amount of dis space equal to ram, 8 gigs of ram saves 8 gigs.
.. 2. Manage your swap file (Page file/virual Memory). Set BOTH MIN and Max to the same value. Windows allocates approx 1 1/2 time your ram. with 8 gigs of ram this is 12 gigs - Savings 11 gigs.
.. 3 Disable restore points, or reduce the sise that it can take - This folder can grow quite large over time.
.. 4 Move c.....Userer\Your name\Mydocuments to the HDD.
Ans to your question - YES you can reuse the Lic Key. Infact until you delete windows on the HDD, you can daul boot between the SSD and the HDD. Just by selecting the F-Key during post that brings up the Boot menu. For Gigabity MBs normally F12, on my Asrock MB it is F11.