As I mentioned earlier, you will have to make sure that BOTH routers have IP addresses in the same subnet. Since you haven't made mention of IP's yet, I will guess they are both still defaulted. You will want to pick an IP address block to use, either the Linksys or the D-Link default will be fine, but you have to pick one or the other.
Linksys typically will use a 192.168.1.1 IP address with 255.255.255.0 subnet mask.
D-Link typically will use a 192.168.0.1 IP address with 255.255.255.0 subnet mask.
Just to make things easy, I would recommend this.... Connect a SINGLE host WIRED to the D-Link. Login to the config page, and make the Router's IP address 192.168.1.2 and the subnet mask 255.255.255.0. You will also want to DISABLE DHCP on the D-Link router.
If that STILL doesn't do the trick, it could be that you will need a cross over cable between the two. I doubt this though, because more new(er) switches & routers come with a feature called MDI MDI-X. This feature auto-detects the cable type, so that if you need a cross-over, but are using a straight through, the hardware will correct it so that the crossover can be used.