I suggest keeping your e-mail account separate from your ISP. Then, if you switch to a different ISP (e.g. to go over to broadband), at a later date, you won't have to change your e-mail address.
For 100% reliable pay-per-minute dial up (at local call rates), simply go to Dial Up Networking on your PC, and create a connection which dials 08456389800, with the username 'guest' and the password 'webguest'. (That's the guest log-in for Webtribe, which is now part of Freewire).
For a free e-mail account (which can be accessed both via the web and via an e-mail client, such as Outlook Express), go here:
http://www.gawab.com/webfront/main.php
Start by clicking 'More countries & cities', to select a suitable domain name. (I've opened dozens of accounts with Gawab. I usually choose '@alex4all.com' or '@gawab.com' but there are plenty to choose from).
Then work your way through the instructions to set up your new account. (When you get to the bit which asks if you object to certain types of advertising, just tick all of them. Then you'll get an ad-free account).
Once you've set up your account, you'll be able to access it via the web. To use it with Outlook Express, go to Tools > Accounts > Add > Mail and create an account with the following information:
Username = full e-mail address (including the part after the '@' sign)
Password = whatever you chose
POP server = pop.gawab.com
SMTP server = smtp.gawab.com
Once you've created the account, click on it and select Properties > Servers. Place a tick alongside 'My server requires authentication'. Click 'Apply' and 'OK'.
Chris