Just what was said. SSDs do not increase FPS. They are just faster storage devices compared to HDDs. The random access time difference is HUGE.
The Samsung EVO models are great consumer SSDs. They are a little more than some of the lower cost ones, but come with some of the best software including cloning software. They also have faster write speeds than most of the other lower cost, smaller SSD's.
Also consider a larger than 120GB drive. The cost of going to the 240/250GB drives is not that much for the extra space. I almost filled up my 240GB drive pretty quickly with games over a years time. Just something to think about.
The Crucial M500 is a good choice as well