Running in general is going to exert significant wear and tear on your joints. As was suggested, getting shoes/orthotics fitted to your foot will minimize this damage. Asics and New Balance are probably the best commercially available running shoes in their higher end models.
The weighted vest/pack is fine as long as it doesn't significantly alter your running mechanics. Bad mechanics is where you really get hurt. If you can handle it just fine, though, go with it.
-Dan
