Installing SSD in Asus laptop - How to activate Windows

I recently bought an Asus N55SL laptop. It came pre-installed with Win 7 Home Premium on a 750GB drive.

I bought a 120GB SSD, and would like to replace the HDD with it. The HDD came with a recovery partition on it, but I don't think that will help. When I started the laptop for the first time, I made Asus recovery disks that can be used to restore the laptop to factory conditions. However, when i try to use those to recover to the SSD, it appears to work, but when it's "setting up windows for first time use" it goes into a rebooting loop. I'm assuming that the disk image made by the recovery program on the 750gb HDD can't be applied to the 120gb SSD.

So, how can I install windows on my SSD using the Win 7 product key that came with my laptop? I tried installing another copy of Win7 Home Premium that I had, but the license key wouldn't work for it. I called Asus support but they didn't give me any useful info. They made it sound like I was the first person to ever want to change a laptop harddrive. Any suggestions would be much apprecieated!