Trying video again

Having given up once before, I'm now having another go at getting
voice/video to work with XP Messenger. Some questions:
1. Do XP Messenger and MSN Messenger use the same protocols and ports?
Can they communicate with each other?
1a. Why when I agree to XP Messenger being upgraded, am I offered MSN
Messenger? Why are there 2 things like this as well as NetMeeting?

2. What ports and protocols are needed? In one place I read that UDP is
used, elsewhere TCP. The list on Jonathan Kay's site doesn't exactly
match the list supplied by the router manufacturer (Netgear).

3. Is there anywhere that can be connected to like a test site with a
camera pointing at the sky and traffic noise (say) so that one can
autoconnect and test?

I'm using a DSL router which supports UPnP with a separate Wireless
router that has all its routing functions turned off (ie it is acting as
a simple wireless access point). The manufacturer tells me that this
removes its firewall, but my wired connection machine shows an internet
connection in the Network Connections bit of control panel, whereas the
wireless machines don't. Also, the wired machine pops up a list of UPnP
functions on the router config , but the wireless machines don't. Is
there something that the wireless network isn't passing? All machines
connect to the internet OK.

Sorry for all the questions. Grateful for any help.

--
Bill Holt