Chaldfont said:
Did you say Catan... Online? Sweet.
You can do that on the PC for free.
Hellhound told be about a site, I forgot where it is, and I can't look it up at the moment, but there are websites where you can do that with a normal PC.
I got a Wii for a low priced gamesystem about a year ago, and it's a lot of fun. It works great on a normal TV, graphics are good (though not great), but gameplay is usually stellar, and it's missing some of the games the PS3 and 360 get. It have the huge advantage of some of the best in house game franchises though. The big advantages the Wii had for me was I had a gamecube and it was compatable, and it had the games I wanted (Zelda & Metroid specificly)
I also have a PC, and I used to enjoy a lot of games for it, but I've found that short of the more involved sandbox games (Like X or Oblivion), it's lacking at times. I don't care for FPS games (Which PCs are very good at), no MMORPGs for me, and I'm not a huge straturgy guy. The PC has been left out of the development loop for a lot of new games that aren't in that mold. There are no college sports games for it, and it's behind the curve in the Pro Sports arena now (and I don't know why).
So, that leaves the 360 and PS3.
If history keeps to itself, the 360 will have a lot more FPS games and support from US game makers, while the PS3 will end up with a few more well rounded games and support from the japanese game makers. The game makers is a big difference when talking about RPGs at least.
So, if you're worried about budget, or want something the whole family can fool around with, I'd go Wii. Beyond that, 360 and PS3 are good choices.
You can build a reasonable gaming PC for $1200 (I did in '06 and it's still can handle anything thrown at it), and that's not a bad option if you need a PC for other things (Said PC I use also does some DVD burning, home video work, web programing, and other fun stuff).
The big thing is to find out what games you want. If there are some PC games, then a PC is a better choice for you. If there are some 360 games you want, then go 360. If it's PS3? Wii? go for that. If they're out for all systems, then you need to fit your budget and needs.
BTW, you'll need an HDTV or converter in the next year or two anyway if you're in the US, so you might want to look into doing that (and it's easier to convince the wife, as she gets something out of it), and you can always sneak in your new consol later.