What kind of router do you have?
Does it have two ports one for the external wan internet? (cable,dsl)
Then the other is a single network connection.
Or it only wireless?
From what I can tell I don't think your current setup will work. You are working with to different classes of IP's. The 172.xxx.xxx.xxx is a class B and 192.168.xxx.xxx is a class C network.
If I understand this you connect the laptop to the windows machine with a crossover cable.
The windows machine has an ip 172.16.1.34 and this is the wireless IP?
Now there is a nic card in the Windows box and what IP is it using?
I assume it something in the 192.168.0.XXX.
If that is so whay not use 172.16.1.100. Then use 172.16.1.159 on the laptop.
Just a thought here.
Quick trip over to friends house to look over the setup I created for him.
1 pc and 1 laptop connect hardwire ethernet to a cable/dsl router with an internal ip of 192.168.4.1/255.255.255.0. All machines use static IP's
ip 192.168.4.100/255.255.255.0 gateway 192.168.4.1(this is the router)
exports file contents
ip 192.168.4.150/255.255.255.0 gateway 192.168.4.1
mountpoint created on laptaop at /mnt/pc_storage1
mount command ' mount -t nfs -o rw 192.168.1.100:/storage1 /mnt/pc_storage1 '.
No firewalls running on either machine since they are behind a router.
Same usernames created on both machines.
If this does not help then the only other thought is setup samba networking.
Hope this helps. Good luck.