Wifi issue between XP pro and Vista home sys

I have connected two laptops thru wifi(peer to peer), but i am not able to access any files or share internet. Both systems are in same work group

Laptop 1 - XP prof (192.168.1.1) - have internet connection
Laptop 2 - Vista Home (192.168.1.2)

Form Laptop2 able to ping laptop1, but not able to ping laptop1 to laptop2


while trying to access laptop 2 to Laptop 1 prompting for userid and password. if give user id and password it is not taking.

anyone please provide me a solution