Help networking xbox

Hi there i have an original xbox and i want to connect it to my PC. I have evox installed on xbox. I have done it before when i was living at my parents but now i have a different set up it will not work and i was wondering if any one could help. The set up i have is 2 computers 1 downstairs thatis connecyed to the router and the 1 upstairs which is connected wirelessly to the router (which is located downstairs). Im just wondering if there is a way to connect the xbox to the PC using a secondary router as the xbox is upstairs in my room along with the other PC. Im guessin the easiest way would be just to use a crossover cable but i dont have 1 at the moment and dont get paid till next month.

Sorry if all sounds complicated or not very well explained. Any help would be appreciated

At present reading from what information you have provided currently, you only have 1 router.

If you want to connect the Xbox up to the network you can use a wired option connecting to the router downstairs or add a wireless card MOD to your console.

Alternatively as you have mentioned you can simply use a crossover cable with your PC upstairs.