If I want to simmer or braise a piece of beef for a few hours, how do I choose suitable meat? Which of the usual cuts are great, which are adequate, and which ones will just turn tough? It would be great if you could, beside giving a list of the good cuts, also give some advice on visually recognizing the good meat, in case I am faced with a supermarket selection with no labels (or misleading labels) and no qualified personnel.
For simmering and braising it's good to choose a working cut, that is from a load-bearing part of the animal, as this will have connective tissue which will break down into gelatin as it is cooked. These make terrible roasts but great braises and stews. The other consideration is fat content - you have to remember in a braise or stew the fat isn't going to be able to drip out, so if you have a fatty piece of meat you could end up with a greasy dish.
In the past I've gotten very good results from shin (leg, foreleg), brisket, flank, and silverside (round). Parts from the neck and shoulder I personally avoid as they often have lots of gristle and fat, making it work to get at the good meat. A decently butchered pot roast would do though.
One thing to remember is to get a good quality meat. In the US most of what you find in the stores is Select grade, which has a huge range in quality, so look for good color with decent marbling. You are getting a tough cut, so when touching don't expect much give. In fact, if you get lots of give with a working cut don't buy it - it's probably old.