well foo, my last post did not take so i will try this again.
1. most Linksys routers are set as a DHCP server as a default.
2. the default IP on the router is 192.168.1.1
with those 2 things being said i will try to help.
1. when you have your NIC set to a static IP, is it on the 192.168.1.x subnet 255.255.255.0 gateway 192.168.1.1?
2. when set to obtain an IP via DHCP did you tell it were to look (give it the gateway IP) of 192.168.1.1
3. when you have a static IP can you ping the router? open a console (or go to a terminal) and type ping 192.168.1.1 you should get a responce. if not you are on the wrong IP scheme and need to figure out what the proper scheme needs to be.
you can do this by hitting start, run, type in cmd, then hit enter (or click the OK button) in your windows box.
this will bring up a DOS type screen. in there you need to type ipconfig (yes ipconfig, not ifconfig like in linux) and read the line that will look like the following:
C:\Documents and Settings\xxxxx>ipconfig
Windows IP Configuration
Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix . :
IP Address. . . . . . . . . . . . : 192.168.2.100
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.2.1
C:\Documents and Settings\xxxxx>
as you can see i have changed my default gateway from 192.168.1.1 to 192.168.2.1.
then you can build either your DHCP in linux, or static IP in linux to match what is WORKING in your windows box.
hope that helps.