Is your media on your C drive or on a second hard drive? If your media is being stored on a second hard drive --
particularly an external hard drive -- that could account for it showing up offline. It could be that, every time you start up your computer, your computer is assigning a different letter to the drive, for instance.
As for yoru crashes, that likely signals a more serious problem with your system. But it's hard to say what without knowing what type of camcorder your video is coming from, how fast your processor is, how much RAM you have and, especially, how much free, defragmented space is on your hard drive. It sounds very much like your system is choking because it lacks hardware resources or because the camcorder or media you are using is demanding more resources than you can provide (as when you use photos that are larger than 1000x750 pixels in size).
I have 6.00 GB of RAM. I don't use a 2nd hard drive. My processor is 2.67GHz. And for most of my videos I use Fraps.
There are a lot of good articles on the PrPro forum about editing FRAPS video. You might want to search the Adobe fora for "FRAPS" and limit it to the PrPro forum. You'll have a lot of interesting reading. It is not an easy format/CODEC to edit, but can be done. Those articles will give you a lot of tips.