Ok, I need a little

here. My Husband and I each have our own computers hooked up to the internet through a router on DSL. His computer is running on XP and mine on 2000. His computer can connect to the internet just fine, but mine can not.
Thing is, mine has been connecting for the last few months without a problem.

I'm wondering if I can't connect now because we are running 2 different operating systems.
I've checked the cables, the connections from the router to the comps and to the DSL box supplied by Verizon and found nothing wrong with the connections as far as what cables go where.
Please

if you can.
Thanks