So I assume you got a new SSD.. installed Windows on it..
Your old HDD is still attached.. but you not seeing your old apps/games? correct?
Well.. if correct.. you have been a bit of a numpty..
Your games will be on the old HDD still - but not recognised.. since they were not installed on the windows installation you now using..
So if you lucky.. if you navigate to where they are on your old HDD and try running them.. they may fix themselves and work.. (Blizzard games are good for working well like this).
Or you may need reinstall them.
If you tell us what you did exactly in terms of how you installed your SSD. .we may be able to give you better advice.
Cheers