vaio vgn a115s,o.s set up.

had to replace hard drive in my daughters notebook,all went well or so i thought! replaced vista and did a clean install of xp but now have two problems,and i'm hoping you guys can give me some guidance (1)on starting windows could not connect via w/less card to internet windows showing no wireless at all and ethernet connection ok,checked front of unit and found w/lan switch was jammed (prob i caused when i replaced hard drive). no lights on so decided to use a belkin w/less usb adapter this picked up and connected to my d/link router ok,but when i took to my daughters house picks up her router asks for password then just gives the continuous connecting signal but does not connect (2)screen brightness cannot be adjusted hotkeys do not work ie fn +f5 what do i need to enable, at the moment wifi is the priority.looking forward to any help you can provide me with.