I recently bought a SSD (well, know that I think, almost a year. Time sure runs away...). It was a Samsung EVO 212, 128 GB edition.
I think that it is, with my mechanical keyboard, the best purchase I have ever made. I have a goodish - decent PC (2nd gen i5, 8GB of cheap ddr3 ram, mid range nvidia) so, even if I wasn't struggling for some speed, using and old, cheap and heavily reused HDD, I saved some money and tried what was the fuss all about.
And personally, I was delighted. Even if it is a "cheap" (70 € more or less) SSD, the system boots in the bat of an eye. Apps load very fast and overall, my Windows felt snappier. I have also noted that the feeling I had with an "old" Windows installation (6 months tops and I felt the need for reinstalling) of becoming clunky, has decreased a lot.
What I did, similar to your situation, was keeping that drive for storage/games* and getting the ssd for windows + apps. I say games* because, even if they would be faster, I want to keep writes to a min, and I tend to keep loooots of games in another old HDD.
You would have to learn a few things about ssd's (no swap nor defrag for example) and calculate how much space you will need. Because high capacity ssd's are waaaaay over my budget at least, so I can't recommend them. But if you can live with less space and can rely on the older HDD for backups, I think a decent smallish ssd won't do any harm. I personally loved the change, but that is my opnion. Take it with a grain of salt.
About classical HDD's, when in need of them, I prefer seagate blacks (for general purpose. You can fine tune the price / performance with greens or whatever). They are the ones that have worked best for me.
Sorry for grammar and typos, I am in a zombie state. (But my opinions are sincere, don't worry! xD)