I am one that has all of the major three systems. I have no negative attitudes towards Nintendo, Sony, and Microsoft. All three consoles are excellent, IMHO. I basically use the GameCube for my Sonic, Mario, and Link games; the Playstation 2 for Twisted Metal, Grand Theft Auto Vice City, World Series Baseball 2K3, and XBOX for Halo, Jet Set Radio Future, Splinter Cell, and MechAssault. Those are just a few of the games I have for the systems. However, they are the ones that I play the most of right now.
My suggestion is always to get all of the major systems, but that is a utopian dream for many, especially for those who cannot afford to get more than a few games for a system as it is in today's economy.
The GameCube may be a"kiddy" system for some, but it has some excellent games, such as Zelda, Mario Sunshine, and Metroid Prime. However, you may have some gripes with Microsoft and those are legit, for you. Afterall, what if you had major setbacks with Windows XP? Your experiences would definitely make purchasing a XBOX a lose situation for you. That is your right not to buy an XBOX. Its your money and your decision.