TF2: Full screen, can't change resolution, game crashes

[Toquita]

Just realised that on Windowed mode it works perfectly, but on full screen the game crashed on the server welcome.
Also, while in Windowed mode it works, if I try to go full screen it crashes too. And I can't change resolution while in-game, but I can change between FullScreen and Windowed, and after it's windowed I can change the resolution.

Game freeze at server welcome: http://img259.imageshack.us/img259/4150/capturadetelade20121228.png

PS: That's not my FPS rate. It stays on about 50 when the game freezes, but normally I get 100-200 fps (All High Quality, 4xAA, 16xFilter, -w 1280)

Sync to VBlank turned off. Preffer Maximum performance On.

[Toquita]

Yes, I know. I had it on full screen before, but what I was trying to say is that I can't change the resolution in-game if the game is full-screen. I can only change from fullscreen to windoed while in-game.