You can get a 200+GB SSD for a reasonable price. And while it might not sound like it 200+GB is a LOT of data. Chances are it's going to hold everything except some media files (Music / Movies). But you can cheaply store them on a HDD or a remote file server. And once you have that file server you can cheaply play those movies at any computer or any PS3/XBOX/iPad/Boxee (etc) in your house which is really nice. So, while it might cost a little extra and take a little more work there is a lot to be said for going down the SSD path.
Of course you can also get a smaller SSD and or use it as your only disk drive, but they do really make that old file server idea really appealing especially if you have more than one computer.
Use both. But the OS and application files on the smallish SSD, and the data on the hard disk. Most "active" data can easily fit in 64G. The rest is stuff that is not accessed often enough to need the speed of an SSD.
By the way, get an Intel or a Samsung when your Vertex fails...