Hi, there are many programs that will clone an entire drive to an SSD. This is safe and effective for win7. http://en.wikipedia.org/wiki/List_of_disk_cloning_software
One approach would be to get an external USB drive, migrate most of your data to the external drive and then clone what remains to the SSD. You could then use your old drive to hold the contnet of the external drive and set up the external drive as a backup device.
I'm sure there is a program somewhere that will split a disk and send only part to the SSD but I don't know of any.