home networking issue

i have an MSI M662 duo core laptop and a MDG pentium 4 3.3 gig i had vista on the MDG and put 7 build 7022 (have 7048 coming in) on the laptop now i have spent almost 2 solid days (no sleep) trying to get these things to communicate so i put 7 build 7022 in the Mdg did all the updates they see each other in the network but cannot access any files and yes the are in the same network and subnet i am using a wireless router with a motorola bridge (WE800G) on the MDG and when i try to exit explorer it crashes any help would be great

i found the problem your wireless must have a good to verygood connection for home group to work