The "failed to connect: connection timed out (10060)" error is a windows socke error (Winsock) which means a connection attempt failed because the connected party did not properly respond after a period of time. Of you haven't already done so do a ping to that target ip address just to make sure you have network connectivitity to the host computer. In any case this is most likely not the problem - the most likely problem has to do with trying to port forward accross multiple routers. We have seen this to work very very rarely.
What you need to do is dump the D-Link router and just get a D-Link switch (these are really cheap we have a 5 port switch, 1 input 4 outputs for $39 here: http://www.rfwel.com/shop/catalog/Linksys-5-port-10-100-Switch-p-695.html. This way you only have one level of NAT (network address transversal) and the port forwarding will work fine.
As an aside remember the only time you need multiple routers in your network is to isolate collision domains. Said simply is when your network is so large (many computers) that you need to separate domains to minimize collisions. Recall that ethernet uses CSMA/CD (Carrier sense multiple access with collision detection) for multi-access control. When one or more PC's on the network start to transmit at the same time they collide (this is expected). When they collide they try again to retransmit but after a random delay called the backoff period. As you start adding PC's to your networks these collisions become more and the backoff time becomes more which manifests itself as a drop in throughput or speed of your network. In this case adding another router helps. So if you dont have many computers then a single router is fine and to connect multiple computers to this single router if you only have one output port you need a switch.
Let us know how your setup goes after you make this change and your video quality through VNC as well as what DVR you are using for your remote camera.
