first check your bios to see if your touchpad is enabled. if thats not it, Your best bet is to switch to windows 7, the generic drivers for it are better by magnatudes. if you dont know how to get that for free you have to plug in a mouse and install Synaptics touch pad drivers manually.
donno if forums allow urls but, just to be safe just do a google search of Synaptics and it should pop right up.