You are considering a .44mag for the extra "boom". Well, let me tell you that a .357mag can make a heck of a racket. When I shoot my 3" S&W 65 and my 6" 586 with 125gr ammo I have people coming by to see what the heck I'm shooting. If you really love recoil a J-frame .357mag snub will really do it (it will rip your hand off and deafen everyone at the entire range
). Shooting full powered ammo, especially the 125 grain variety will give you a good "boom" and if you want something extra you can get the 180gr hunting rounds.
The versatility of a .357mag is hard to beat. You can shoot .38spl wadcutters for plinking and target shooting, in cheaper .38 loadings only 9mm will cost you less in centerfire calibers, yet there are good .38spl defensive loadings should you decide to occasionally use this for home or personal defense (trust me, you probably will), there are even better +Ps and then you move into the range of choices in .357mag (110gr personal defense ammo, 125gr ammo that is among the best defensive ammo made, 158gr ammo which is the original and the 180gr hunting stuff).
Also, what about Colt's vs S&W?
Well, I have a Colt Police Positive Special (.38spl) which I love but for a first or only revolver I'd go S&W, Ruger or Taurus. The lockwork on the Colt isn't as strong, the triggers generally aren't as good and are harder to work on, there aren't as many gunsmiths who can/will work on them, etc. Some very nice guns, but I think they are better as second, third, etc guns in one's revolver collection.
Which makes and models? Well any from the big three (S&W, Ruger, and Taurus) in a 3" or 4" medium frame (K or L-frame in S&W sizes, or equivelent) would do nicely. These will handle most any .357mag loading fairly comfortably, they are durable, lighter than the large framed .357s (more comfortable for extended range trips or should you ever decide to carry it, which, if you can, you probably will at least occasionally). The 3" or 4" barrel length gives you a good sight radius yet they are plenty short for concealment.
More specifically I like the S&W 65 (I have a 3" 65LS, the 65 is a K-framed fixed sight revovler), the S&W 66 (same as the 65 but adjustable sights), the S&W 13 (the blued version of the 65, only available used), the S&W 19 (blued 66, used only), the S&W 586 (L-frame which is a bit bigger/more durable than the K-frame, mine is 6"- these have adjustable sights), the S&W 686 (stainless version of the 586), the S&W 681 (used only, fixed sight version of the 686, the 581 which is blued is too rare and usually much more money), the Ruger GP 100 (roughly a L-frame sized gun, available blued or stainless with either fixed or adjustable sights), the Taurus 65 (6 shot, fixed sights, K-frame equivelent, blue or stainless), Taurus 66 (7 shot, adj. sights, K equivelent, blue or stainless), and the Taurus Tracker (L equivelent, I think it is 7 shots, adj sights- stainless or Titanium only). Basically, that is all K-frame and L-framed sized .357mag revolvers from S&W, Ruger and Taurus.