Skimby :
I decided I'm going to get 2 hard drives of 1TB each. That way, I can use one for games and the other for mass storage. My question is: do I REALLY need to use RAID or is there the option to run both drives separately?
2 individual drives!
RAID is NOT necessary, nor desired.
For Steam games, you can easily designate other drives as the install location:
Steam games location
In the steam client:
Steam
Settings
Downloads
Steam Library Folders
Add library folder