Bush-league question: XP PPPOE/DHCP Drops connections

Hello all,
I have a Dell Latitude running XP Pro/SP2, and have a 2wire wifi card. I
used to be able to connect without any problems to just about any wireless
network (hotspot) using an older Netgear setup. However, six months ago I
installed the new driver/software for the 2Wire Wireless card, router and
associated manager. This supported my home DSL network: wireless for the
laptop, ethernet for my Optiplex server. Both worked fine. No problems. Very
cool.

However...

Since then, I can not connect to any network other than my home network
without the connection dropping over and over and over again. It searches,
finds, connects, authenticates, opens Internet access for about ten
seconds... then drops.

Constantly.

I have tried every sort of Simple-Simon solution I can devise. Even went so
far as to uninstall and reinstall the 2Wire software and eventually XP. I
think I've spent more time reconfiguring my networking than I have working of
late.

For a while, I thought it was something to do with DHCP... as the lease
obtain/lease expire was often set to the same time. (Of note, when the help
files say, "Contact your system administrator." under the assumption that
such a person exists... it makes me grumble loud and long.)

However, after spending too much time reading posts and pondering the Help
index, I now think that perhaps when I installed the 2Wire software that it
added a PPPOE something or other and that the XP and 2Wire PPPOE software are
creating conflict.

Question: does this make senes? Would it cause the behavior I'm describing?
(It blows out ethernet as well.) How do I uninstall one/the other of the
PPPOE doodads without uninstalling my wireless router software/messing up XP?

I have a new ISP... using a cable modem with an additional home network box
running 2000.

I'm a fairly basic user, so please be patient and use small words:-)

Thanks for any help!

D