Dialup Password problem

I have just bought a new PC running vista with a talktalk dialup broadband
account accessed via a Speedtouch 330 USB router. I have been trying in vain
for several days to set up my internet connection on my pc. I can access the
internet but the dial-up connection program refuses to remember my password,
so each time I access the internet I have to enter the password manually. I
have attempted to set up the account in vista via the internet and network
connections in the control panel ... I tick the boxes "remember my username
and password" and "allow other users to access this network connection" I
have no problem with the first log on but the next time I log on the password
needs re-entering manually ... The log-on is not accessible via other
profiles. I have a user profile set up for other family members with limited
accessability and want them to be able to access the internet via my log-on
without having to type the password in manually .....
I am considering buying a newer router with an ethernet connection but am
concerned that I will have a similar problem with this .... I am getting
really frustrated
Help me ... please