Glasses
It's a jungle of stemware out there, with many manufacturers making claims for the scientifically engineered appropriateness of their glasses. There's no question that the shape and dimensions of glasses changes the way wine tastes—it's just unpredictable how any glass is going to interact with any wine.
There are only two principles to live by: Make sure the glasses are large, and make sure to fill them not more than a third of the way up. This enables swirling and maximizes the amount of oxygen you'll be able to drive into your wine at drinking time—which will maximize your olfactory pleasure.
Broken Corks
If your cork breaks while you're opening a bottle, do not panic! The worst that can happen is that a little cork will get into your wine. First, try to save the day by attacking the remaining cork from odd angles with your corkscrew. If that doesn't work, simply push what's left of the cork into the full bottle of wine, then strain the wine into a decanter.
Oxygen
Do wines need to breathe? Most don't. If you're serving an expensive, top-level red wine that is meant to age, and if you're serving it young, giving it some air will accelerate the aging process by oxidizing it. This will bring it a bit closer to what it might be ten years down the road.
This is one of the main reasons why people decant red wine, spilling the wine out of its bottle and into a glass pitcher (usually a very tasteful cut-glass pitcher). Pouring exposes the wine to maximum oxygen; some servers even pour it back and forth between two decanters, thereby increasing the oxygen exposure. You may want to try this if you have a very young, very tannic red—say a Cabernet from Bordeaux or California that's not more than one to two years old.
