Alex,
It's strange because it is slow but works. If your server is your DHCP server, then your DNS should point to the server, e.g. 192.168.0.101. Of course if your server were your DHCP, then the DNS would be 0.101.
Your server should also be 0.101 for your DNS and WINS servers. This, again, of course if the server is the DHCP and not DHCP enabled. Your server should have a static IP and when set up should have the settings with the 101 DNS.
If you are using your router for DHCP, I would turn that off and turn DHCP on for your server. If you are using all static IPs, I would definitely make all of your clients DHCP.
It appears as though you may be using your router.
