While there may some generally agreed upon typical usages, each mic has strengths and weaknesses that make it unique and applicable (or not) in a variety of applications.
Generally, a large diagram condensor would be the first choice for a lead vocal. That's not always the case though. I've read that Steven Tyler of Areosmith has used a SM58 on some tracks. The first verse of 'Life is a Highway' by Tom Cochran was the demo version using either a SM58 or 57. The rest was replaced in the studio by the label producer (and Tom) using the aformentioned large condensor, probably a Neumann of some kind. Micheal Jackson's vocals on Thriller were recorded using one of my favorite dynamic mic's, the Shure SM7b. Sherly Crow has also been recorded with the SM7.
I've recorded guitars using dynamics (SM57, SM58, Sennhieser MD421, others). Recently I started using small omni condensors about 18" back and I'm really pleased with the results. Typically, those mics are used as drum overheads.
Speaking of drum overheads, typically (as already mentioned) small D condensors, either directional (cardioid) or omni are used, depending on the room. However, if you take a look at the latest Led Zeppelin DVD, during the Royal Albert Hall recordings there are dynamics (EV RE20's) as overheads on Bonham's kit. They sound amazing.
So, the rule is: There are no rules.
The generally agreed upon norm's are good to research if you want a starting point. IMHO the best way (already mentioned previously by justinf) is to learn what sounds good by experimenting with what you have. Use what sound's good and don't worry about it.
There's a lot of useful information about micrphones and their usage on the microphone university section of this site. (I'm not affilaited in any way)