Re: Water Spots on new black car
If you've waited 4-5 days to address the spots, they'll be harder to deal with than if you had dealt with them that day. Quick response time is key.
Forrest's first 2 suggestions won't dull your paint. In fact, the instant detailer will help boost the shine (Mothers will, at least).
As to the vinegar wash, it's also known as an "acid wash." Now before you get worried, vinegar is fairly mild. We're not talking about hydrochloric acid, or anything that'll eat away your hands and car. It's just that mineral deposits "respond" better to acid vs. alcali washes.
If you haven't already done so, wash the car with car soap first, to get rid of dirt/dust already on the car (I'm guessing you would have already washed it, as that was Forrest's 1st suggestion). Then use the vinegar. Think of it as a chemical wash, not a mechanical one. Let the vinegar disolve the spots. Don't rub vigorously. After ridding the paint of the spots, re-wash with car soap.
You might notice the paint looking a little dull, from less wax. You can then proceed to use whatever your favorite wax is. If you happen to be out of wax, I'd suggest any of the Mothers line. If your paint is in "less than optically perfect shape," you should polish first. If you want to go "whole hog" then use the 3 phases (PWC,S&G,Wax). If you want to be done after a once around, you can use either Mothers Original Carnauba Cleaner Wax® or Reflections®. Reflections® has a broader range of working temps than the wax, but if you have shade, or it's not too warm out, either will work well.
A person who is aliterate is no better off than one who is illiterate.