PC can't find network device

Dimension 8300 / 2350 router

Hope this is the proper forum for this question.
My PC can't seem to talk to my Tivo DVR. On the DVR, I get a message it can't find the PC. On the PC I get a meesage stating it can't find the DVR. However, the router was able to send the DVR an IP address and a MAC. Signal strength on the DVR is listed as 'excellent.'

Here is what I know.
Setup
Dell wireless broadband router
Dell desktop PC connected to router by ethernet
cable modem connected to router by ethernet
laptop connected to router wirelessly with a Dell wireless adapter.
Tivo DVR connected to router wirelessly with a Dell wireless adapter.
Tivo can receive and send data to my laptop - from this I conclude the DVR router is working correctly.
Tivo can neither receive nor send data to my PC
Tivo, laptop, and PC can all communicate through the router to 'outside' the network.
I can share files/folders between the PC and laptop

I have unistalled my Norton Firewall from the PC
I have disabled my Windows Firewall
I have disabled Norton Antivirus
I have unistalled/reinstalled the Tivo sw numerous times.
None of this helps.
I have checked the Tivo sw installation on the PC and laptop. These are identical with the exception of the network devices (PC uses an internal card, laptop uses a USB adapter). When I open the Tivo sw on the PC, it has the name and IP Address on of the Tivo DVR. Since I did not enter this manually, I presume the PC and DVR can communicate enough to let the PC know the DVR is on the network.

A Tivo rep says the problem is with the router - I need to tell the router to accept communications from all network devices individually by telling the router to open specific ports.
Dell rep says this is incorrect - the router restricts NOTHING within the network - all communication is allowed.
Nonethless, I tried enabling DMZ on the router. No difference.
I tried to open specific ports on the router. No difference.
Since I know very little about networks, it seems to me if Tivo can comunicate with the laptop the router is not the problem (unless the Tivo rep is correct).

I have tried the following from the Windows command screen

from the laptop
ping to PC - sent 4, received 4, lost 0
ping the tivo - sent 4, received 4, lost 0
telnet to tivo thru port 80 - I get a blank screen (I'm told that's good)
telnet to PC thru port 80 - 'could not open'
telnet to tivo thru port 443 - blank screen
telnet to tivo thru port 2190 (this is the port Tivo claims to use) - I get a series of cursor-like underscores down the screen
telnet to tivo thru port 8080 - (this is another port Tivo claims to use)- 'could not open'
But, the laptop and Tivo communicate

from the PC
ping the laptop - sent 4, received 4, lost 0
ping the tivo - sent 4, received 4, lost 0
telnet to tivo thru port 80 - I get 'could not open'
telnet to laptop thru port 80 - 'could not open'
telnet to tivo thru port 443 - blank screen
telnet to tivo thru port 2190 - blank screen
telnet to tivo thru port 8080 - 'could not open'

I have been told VPN sw will block ports. I don't know how to check my PC for this.
am willing to listen to any suggestions or tests.

So the obvious question - is there something in the PC that is preventing it and the DVR from communicating?