A quality SSD doesn't have to cost all that much as long as you don't demand a large capacity. 64GB is enough for your OS + related data + core software and maybe a game or two. Move your documents/pictures/etc folders to your old hard drive.
I recently got a 128GB Samsung 840 Pro series, only $120 and it came with a free copy of Asassin's Creed 3

. Drive has great reviews and seems to have a solid lifespan. Did I mention it's fast? Windows boots up in seconds and my PC is useable instantly, unlike before where I had to sit and wait for a minute or two after logging in before I could actually use my PC (yes, even defragged/optimized)
Go with Intel (most expensive) or Samsung (not as expensive but still very good quality). Avoid OCZ like the plague. Other brands, check customer reviews before buying to gauge reliability.