i guess my main concern is, when i install the ssd, will i have to reformat the hdd so it doesn't have windows on it anymore?
Eventually, yes. Just to reclaim that space.
So, what you do is - Prep everything before the SSD install.
Save all your personal documents to a folder tree outside of the current Windows install
If you use Steam, save the SteamApps folder there as well. That holds all your games. Similar with Origin.
Install the SSD
Install the OS
With a 128GB (like I have) you can actually install more applications than you may think. So install a bunch of your applications on the SSD as well
So, now that you have the actual system up and running, you can point the Steam client at that location on the HDD. The actual games can live on the HDD. Or both.
Blow away the Windows install on the HDD as necessary. Doesn't necessarily have to be reformatted. But you should probably go in to Disk Management and remove the original System Reserved partition from that drive.