Drivers are part of the OS, so they would go there. The OS had better be Win7; that's the earliest version that implements the necessary TRIM command.
Some people swear by putting the paging file there; some swear that putting the paging file there will kill the drive.
The SSD optimizes whatever you need to read often and fast. For most of us, that's application loading and bootup. If you have a big enough SSD and do a lot of video editing, you could put your video files there. If you run a web server with lots and lots of traffic, and can afford a big enough SSD for your entire database, you'll serve pages faster. If you are serving 1 TB of data for a pattern or constant small reads, buy a 1 TB SDD.
Seriously, it depends on what _you_ need to be read often and quickly.