Computer wont reboot from start menu

[Carl29]

Hi, I've just installed a new motherboard/CPU and, and power supply on my pc, and at the same time i've also installed a new winxp pro installation.
Everything works fine: The only thing is that when I go to "start > turn off" and choose restart; the PC starts to turn off everything just like normal till the blue microsoft windows screen , and then it stays there. Basicaly the pc wont restart, but it turns off normaly when choosing "turn off" .

After inomerous trys I went to the component store and we find out that by removing my old tv tuner from my MO would fix the problem; everything was running great.
I came home, conected my screen, my mouse, and again "it wont reboot"
I really dont understand, it s very weird, the only diference is the my mouse and keyboard, wish are wireless:

What it could be?

thanks

[migmoto007]

try turning on the guest account when your done log off and click turn off computer then use that thats what i told my mom to do cause one time when i was 9 years old i started to get into a game called world of warcraft amd it caught DELETED CAUSE my mom dad thinks swich users means log off but it dosent he thought the world of war craft was the backround he swiched users and the next thing you know boom when he turns the computer off it disapierded and i got real mad and it took up alot of memory eh so i installed all over again bu know im 23 years old.