Even if you leave it like it is, I doubt you'll get every other wardriver jumping on your router. Most are simply looking for free internet access, and won't want to spend the time trying to break WEP, etc. However, living near a university, better safe that sorry. So enable MAC filtering...and spamdies, that's a good idea, changing the WEP key every few days.

However, there's one factor that has not yet been mentioned. If your neighbor happens to have a router, and has not taken proper security precautions with it, you can feel safe. As I mentioned, most wardrivers are looking for free internet acess and will take the easier route. If they have a choice between your router with WEP, and your neihgbor's good ol' linnksys router with all the default settings, they'll go for your neighbor's router 90% of the time.

Better safe than sorry though.