I have been thinking on bying Doom 3 BFG edition but there is one thing stopping me. I dont know if i can play doom 1 and 2 on my computer so what i wonder is: Can my computer be "to good" for doom 1 and 2?? (I have a taurus experienced gtx 750 TI)

I'm running Doom 1, 2 3, Heretic and Hexen on my i7 3960x, a GTX 780 and 8GB RAM using 64bit Win7. All of these games, except Doom 3, would require DosBox, but by purchasing them from Steam, that little drawback is taken care of. I imagine Valve is using some form of DosBox, but it's all set up when you buy it.

Another alternative would be to play Doom 1, 2 and the Heretic/Hexens with a source port such as ZDoom.

DosBox and the source ports are made to allow the games to run on modern OS's. I'm not sure if modern hardware is a drawback at all.

If i buy it im buying it on steam so i guess i just buy it then??

Sure. It'll work fine. If you want a few more modern features like mouse-look, get a source port, install it and just copy or move the wad files from Steam into the port folder, and play the games from there.

Thanks