Networking help please

[crashwg]

After rearranging a bit in my little apartment, I've got to redo my networking to have a minimal number of wires strewn about the place.  I've got an idea of how I want to set this up, but things aren't working the way I had hoped they would.  Then again, I'm no network administrator...

So what I've got is a Westell D90-327W15-06 DSL modem/wired and wireless router combination and also a Microsoft MN-100 wired router.  What I am trying to accomplish is:
"Westell" needs to be on the East wall, where it will serve two XBOXs (one up and one down stairs) and be the wireless access point (PSP, NDS, other?)
"Microsoft" needs to be on the West wall, where it will serve two computers.

What I've done is connect the "To Modem" port of "Microsoft" to a ethernet port of "Westell". 

With it connected like this, a computer connected to "Microsoft" can access the internet, "Microsoft" 192.168.2.1 and "Westell" 192.168.1.1 but not the XBOX 192.168.1.43 (assigned by "Westell").  The XBOX (w/ XBMC) can connect to the internet (ticker is running and weather works) but when trying to access shares on the computer "Workgroup not found."

I can only assume there has to be some setting on "Microsoft" and/or "Westell" that I need to turn on or off...  What do you all have for me?


[edit]
Would this be easier with a switch or hub?  If so, would that defeat the purpose of having a router altogether?
[/edit]

[Samstag]

Turn off the DHCP server on "Microsoft" so that "Westell" takes care of it and puts everybody on the same subnet.

[saint]

Don't use two routers. One router plugged into your DSL modem (or the DSL modem/router combo). The other upstream device should be a switch or hub.

[jbox]

Have you tried turning it off then turning it on again? 

Seriously though, the key issue here is that most (all?) routers treat those "modem" ports very differently to the "LAN" ports, and conceptually connecting through one of those means you are connecting to "the internets", not just "to another LAN". Based on the handful of different set-ups I've wrestled with over the years both for friend's & my own home, the easiest solution for a home is usually to convert all the non-modem routers to simple switches by turning off their DNS servers (or changing them to "DNS relay" from the main router).

It's a bit more fiddling around at the start (like setting each of the routers IP's manually) and you obviously need to make sure you have a spare copy of any important settings in case you have to reset the router's settings when you make a mistake. But once that's done I've found it much easier to have people come around and plug in to any port or wireless and everyone can always see each other (and use the web) without any problems.

edit: in other words, what saint said, except you can convert routers to switches by taping over the modem port and then switching their DNS to relay-only from the main router.

[Ed_McCarron]

Just ignore the WAN port on the non-modem connected router.  Turn off DHCP on this router, and connect the two routers together with a crossover or via one of the uplink ports.

I do this to use an extra router as a dumb access point quite often.

[knave]

I'm pretty sure that a home router is not going to have an uplink. (as I say never having seen it) but yes you should be ok if you turn off the DHCP and use one of the 4 data ports.  (this is in essence using it like a swittch) or you can get a cheap 5 port switch for ~$20. Stay away from hubs...

If you have a computer recycling center you can gett good deals on switches there.
(or just use the router) 

[Ed_McCarron]

Linksys calls it uplink, its just one of the ports duped as a crossover.