My new Vista stop working !!!

i`ve used vista bussiness,and i usually connect to internet at night.but it usually hang up. my pointer can move, but IE stop responding. my clock at side bar stop too. i`ve no other option but to restart. at the restart, it has no send information just like xp did.and my computer setting is just like before i connect to internet. how can i sove this problem?it`s annoying