Yes, stick with an SSD. Tom's Hardware has had countless articles on their front page showing SSD's performance and how beneficial they can be to builds.
Your certainly want your OS installed on the SSD, and then some of your regularly used applications and maybe a game or 2 as well
An i5-2500k sounds like its going to be PLENTY for your uni work. Unless your doing some design engineering/CAD work or video and photo editing requiring huge processing power and extra threads for rendering, save yourself some money and stick with the i5 - In games and about 95% of applications your going to see exactly the same performance.
ATI 7970 (~$550) - Cheaper than the GTX 590, much less power consumption, plenty powerful enough to play all current games maxed out at 1080p.