I think you owe it to yourself to take it to the local Rolex dealer and say "this was my grandfather's watch, I think it's awesome, I would like to wear it in a responsible way that will not harm it, what should I do to keep it happy" and they will say "welcome to the family you are our favorite form of customer excuse us while we all geek out about your watch go over there and look at new rolexes for a few minutes and then come back so we can all be excited about this marvelous ancient treasure together." An overhaul should be $400-$600. Fixing the back shouldn't be more than a couple hundred. The oil used in watches gets kinda funky after 10 years; it won't hurt anything but a 10-year overhaul cycle is de rigeur.
You've convinced me. This place is right around the corner from the office I'm supposed to be working at today, so I'll put on a proper pair of trousers and head out. Also, you've had what sounds like a colossally shit week. I can't say much other than that I'm always grateful for the chat and I hope things turn around for you asap. Next time I'm in the US we seriously need to have beer.