Yeah, if you click on a match server, you wont be able to join it without a password, If your American/Canadian Try the Three Inches Of Blood Pub or Any GT Pubs, they usually have people in them, and are not password protected. If you are European, There's OTB servers and Arctic Servers.
Login has been failing for me and alot of other people lately, sometimes if it just wont log you in, click esc and it brings you to a PLAY SETUP QUIT menu, then just go to a server and play. It might kick you, it might not. I rarely get kicked from it if i cant login.
Another problem could just be to many colours in your name as idas said. Try putting your name white.
Also, if you plan on sticking around try to get IRC or mIRC to connect with the entire dp community!