Assuming that the SSD is 120 GB or greater .... I would.
1. Disconnect the HD data cable. Install SSD and connect to lowest numbered SATA port
2. Do a fresh install of Windows to the SSD.
3. Stop WU from installing hardware drivers
http://www.sevenforums.com/tutorials/82137-drivers-turn-off-automatic-driver-installation.html
4. Install original drivers from media that came with hardware.
5. Run Windows update as many times as it needs to say "I'm done". Reboot and shut down
6. Connect HD to 2nd lowest numbered SATA port
What you have now is a system that can boot off your SSD or ... by changing the boot order in the BIOS, boot from your old cluttered up OS install. The SSD will boot faster not only due to the faster SSD but also because it's a fresh, clean install. But if the SSD dies, or OS gets infected, you can still boot from the old OS.
7. If you install your programs / games right over themselves in the same folders as they are on the HD, you can run those games / programs from either boot.... and all your installed customizations will remain, toolbars, etc will remain