I can't even begin to tell you how amazing an SSD is. Seriously the best $100 I've spent on computer parts in years. I got a 60GB OCZ Vertex 3 for about $80 and haven't looked back.
My own setup is the 60GB Vertex 3 as my Windows 7 boot drive and a 1TB Samsung Spinpoint F3 for data storage. Works flawlessly. If you have ~$200 to spare I can't stress enough how much better this (at a minimum) combo improves your quality of computer use.
To give you an example, my computer goes from power off to the windows desktop in about 21 seconds and my slowest loading program AIDA 64 loads in four seconds with all others (firefox, Internet Explorer, etc) loading in one second on average.
Now obviously the only time my computing experience is just like everyone else is when I'm loading a game off my HDD because it's not on the SSD but that is because I got the cheap 60GB version instead of blowing $250 for a 240GB Vertex 3 that would have enough room to put my games on.
To summarize: buy an SSD.