This will come down to personal preference and the capacity of your solid state drive, but personally I recommend putting your most frequently used programs (i.e. web browser, email client, general startup programs, etc.) onto the SSD. For example, I keep Google Chrome, Thunderbird, Pidgin, Steam, Battle.net Desktop App, et al. on my Samsung 840 PRO. Some of those programs run automatically at launch, and others are ones that I'm likely going to be opening shortly after startup. I want them to come up quickly and run fast, just like my OS. Altogether these programs consume less than one gigabyte of space, which I'm more than willing to spare.
For what it's worth, I also keep my browser's web cache on the SSD. My secondary HDD already has quite a bit of lower-priority, high-I/O stuff running on it, and I keep my tertiary hard drive free from general heavy disk activity but instead dedicate its use to several other programs/games. The web cache can grow large, and it does use up a good chunk of writes. Your best bet is to look at your configuration and decide which option would be best for you. Do you prefer the marginally faster loading times, or would you rather free up a bit of space and lower the strain on the SSD?
As for your GPU drivers, any and all drivers will be automatically installed on the SSD. Accompanying programs (i.e. Catalyst Software Suite/NVidia Control Panel) may not be. I keep those sorts of programs on my SSD as well, although I have installed them to a secondary HDD in the past.