Unlike semiautos I'm not sure if there is such a thing as a bad revolver. Most all of the major makes on the market are reliable. The Smith is the most refined (and it is now American owned again- the people responsible for "the agreement" are gone- THANK GOD), the Ruger is probably the strongest (their small frame SP101 in .38 had to undergo virtually NO modification when they brought it out in .357- that is one strong frame), the Taurus is now a very good gun and significantly less expensive than the S&Ws they're based on, the Rossi is reliable (esp. now that it is made by Taurus- and its certainly reliable in comparison to semiautos) and it is VERY INEXPENSIVE.
For your uses (home defense, target, some concealed) go with the 4" and for some models try even the 3" (I have a 3" S&W 65 in .357 that is as accurate as any gun I've owned, more concealable than all but a 2" snub and very comfortable to shoot). Like any other gun try several out to see what you like.
What do you need. Do you beat your guns up? No one can beat the strength of a Ruger. Do you want something reliable but that is pleasant to shoot? Smith or Taurus. The Taurus may be a little less refined but it may also be a little stronger. Do you want something inexpensive? Almost all are relatively inexpensive as guns go, at least in comparison to comparable autos, but you can't beat the Rossi in price and Taurus are good buys too. Do you want light? Taurus was the first with a titanium frame and Smith just came out with them recently.
Personally, my favorite .357 is my S&W 65 (k-frame) with the same grips as the Ladysmith (I would never own a revolver with rubber grips). It is the most accurate .357 I've shot in a long time. It has only a 3" barrel so it is concealable (so if I ever move out of Maryland so I can get a CCW I can carry it easily), and yet it is a very comfortable .357 to shoot (granted a 4" barrelled k-frame or any heavier frame Smith may be even smoother- it just wouldn't be needed and you'd lose concealablity).
If you are mainly a semiauto guy but just want a revolver to round out your collection then buy what you like best. There is no reason to worry about which is best since most are good selections and you're not likely to use it as your main gun. If you don't have a preference and just feel that you need/want a revolver to have a more complete collection then go with the Rossi or one of the less expensive Taurus revovlers as they are both decent and can be downright cheap (in price anyway). If you are one of those guys who must have the best, then good luck because (of the major brands) Taurus, S&W or Ruger can fit the bill depending upon your criteria. Also, just like autos, if your budget is virtually limitless there are several higher end manufacturers you can go to if you don't mind parting with a small fortune.
If you said you only wanted a target gun that may double for home defense I'd say go 6" or longer, though a 4" would certainly do. However, since you say you may use it for carry I'd stay away from anything more than 4" and (at least in the case of the S&W 65 or the similar 66 which has adjustable sights) a 3" should work for you.
I guess I'm no help. However, unlike autos, there are very few truely BAD choices with revolvers and most all have their strengths.
