The solid state drives are wonderful, and so fast. How big is the one you installed? Don't forget to change the install path for most programs as they will want to install on the "C" drive, and if you have a fairly small SSD you won't want them taking up unnecessary space.
Some programs will benefit from being installed on the SSD, but many will not really take advantage of the extra speed of the SSD and can be installed on the HDD without any speed of access penalties.
Windows 7 should, by default, turn off defrag on the SSD drive, but you want to check just to be sure.