The SSD will speed loading of your games a bit if that's important to you. I don't think it will have much effect on playing.
But the SSD will definitely improve overall "responsiveness" of your system.
60 GB is enough for most situations. You can install games on the HDD if need be to save space. Windows itself takes under 20 GB. I have 55 applications installed on an 80 GB SSD and have only 28 GB occupied.
The hot recommendations are Crucial M4, Intel 320, and Samsung (I think the 830 series?), but any of them are way way way faster than your HDD. Shop by reliability/freedom from problems/support/price.