Okay so I finally get on Live last Friday, have an infant and have not had a reason (pre-Halo2) or time to get on Live. I played all night, since then I have not been able to get back on, and I have done nothing different.
I have an older AMD 1Gb system running Win 98 (soon to be XP), although this should not matter, running through a Linksys WRT54G wireless router with updated bios connected directly to my Motorolla cable modem and my computer. I then have the XBox connected to my Linksys WGA11B wireless game adapter. I have the basic security on the router/game adapter and it is set to the IN channel. I have went and opened up ports 88UPD and 3074UDP/TCP - although I can not see where it says these ports are opened - and this worked fine Friday night, but Saturday morning nothing.

Any ideas? Thanks I really need to get this back working.