These are the disks in the computer:
Primary: Serial ATA up to 120GB at 5400 RPM or 100GB at 7200 RPM
Secondary: Parallel ATA, 80GB at 5400 RPM
The SSD that you are considering is a SATA SSD.
This means that you can swap the primary (existing) SATA hard disk with the new SSD. The way to do this is by cloning the existing SATA drive to the new SSD drive. This can be done by using Apricorn's Drivewire: http://www.apricorn.com/product_detail.php?type=family&id=39
The instructions and procedures are very clear in the manual. (I have used this to successfully replace and upgrade hard disks from one laptop and 2 desktops).
After cloning, you replace the existing SATA disk with the newly cloned SSD.