The easiest (most reliable) solution I can think of but takes an extra step is to use your 2 HDD in the same format you would for a separate OS drive (which will be your ssd eventually) and the other hdd.
Step 1 Setup your 500gb as the OS only drive. Step 2 Point all data (games) to the 2TB drive. Step 3 Clone your 500GB OS only drive to your 120GB ssd; I use Acronis Premium and the cloning tool scales everything perfectly for you. After system shuts down and completes cloning process, disconnect your 500gb drive and turn your system back on. Your system should be running perfectly. Reconnect your 500GB and use that as a tertiary drive, internal back or whatever you want.
Summary: You will have your SSD with OS only (C Drive), 2TB (D Drive), and 500GB (E Drive). The letters may or may not match (of course the ssd will be "C" for sure though). The 2TB should hold all of your current game data etc. You should be now good to go!
Notes: If you want to use freeware make sure you do your homework. I paid the $40 for Acronis Premium 2013 when it was on sale and have enjoyed it. Just sharing what I've done for myself and for customers.
Have fun and good luck!
There may be easier or faster ways to do this and as I'm thinking about it, depending on how you already have things setup this way I'm recommending may be more work for you than it's worth if someone else has been through a similar situation and can recommend what they'd do by all means remain open that instead. However, this said, it should work flawlessly but it's up to you to decide whether it's too hard (in terms of time cost) versus just a fresh install on the SSD and just redirecting everything (pointing to correct drive paths etc.) may be easier or what you'll end up doing. Not sure how you have it all right now but if I'm reading this right, my recommendation shouldn't be too difficult on you.