If you don't already have an external backup, a USB 3.0 enclosure is a really good use. You might not be able to save everything from your primary storage drive, but you can pick the irreplaceable items and then put the spare drive somewhere safe for peace of mind.
If you already have a backup of some sort that you are comfortable with, I say that you download Lubuntu 64-bit. There is a perception that it's only useful for older, slower machines, but the truth is that it really can be a great option for any system. Even on my performance rig, I have 20gb of the SSD partitioned off for it. If you're in a hurry to get online and get some information, play MP3's or watch videos, it's so much more snappy than Windows 7 that it's amazing. Having a totally independent drive is sort of overkill, but it does eliminate the concerns of altering your current OS partition table.