That doesn't sound right. That's the main job of the router, it blocks crap it lets you control ports. I'll look for the manual.
Meanwhile, do you have windows XP? Check for software firewall: start->control_panel, double-click "local area connection" Advanced Tab, is there some Protect blah blah checked?
Edit: I found the manual, no need to take a picture, stand by....
Edit again: There looks to be a place where you can specify a range of ports. I downaded a manual from here
http://www.dlink.com/products/support.asp?pid=62&pv=16 In the configuration software, hit the "advanced" tab and the "Virtual Server" button. In there, create a new service and specify a range of ports using the hyphen to join them. I'ts on page 23 and 24 of the manual. I see you live in Colorado, you can call me if you like in the springs, 719-520-9283.
Edit again fat figered the number fixed now.