SSD's are getting cheaper in price as time goes on, but in my opinion it is still not worth using a high-capacity SSD.
I would stick with a 128/256GB SSD, for your Operating System and apps/some games. With the HDD as a secondary drive for storing media and less-often played games.
---In terms of games, it will only help the initial load of content, afterwards the levels are cached and will not benefit from a HDD over a SSD.