Wireless Internet: Public Wireless Access Problems

Public Wireless Access Problems

I have a Compaq Presario v2000 runing Windows XP and I am generally very happy with it. However I have two problems that I can not seem to find the answers to.

I travel a lot and use public access wifi to check my email. Some places I can not access the internet. I will connect to the wifi router, but there is a lock going from the router to the internet as if it is ecripted and needs a password, but it never asks for one. Sometimes I get a firewall message, and turn off my windows firewall. Usually this does not fix my problem, but it does sometimes.
The next trip I may not have a problem at the same location. (Right now I remember JFK Airport as one place). I had Norton on this machine, but I went to their site and un-installed it. I use Windows firewall and AVG free antivirus. Is it possible Norton left some sort of firewall in place? It may have started when I changed to AVG?

My second problem may not be wifi, but I'll ask it. I used Sony Location Free TV (remote access to my cable box over the internet)for some time. Then the program stopped loading. I get the error message "failed to initialize Direct X - error code 0200101636024." Sony Tech suport said "not me" but did show me how to troubleshoot Direct X. I even reinstalled an updated Direct X. No help. All other programs run fine.
I hope someone can help me - I will greatly appreciate any info you can give me. I am semi-computer illiterate, so please keep it simple!