No ISP is perfect and I'm sure others will argue against my choice.
I signed up for Pipex Homecalls up to 8mb package which includes calls & line rental
I pay £10.99 line rental, £12.50 for calls (its curently £6.25 as an offer if you sign up now) and £6.50 for the internet. They have packages for heavy internet use, but as family we get by fine on the cheap package - all in for £29.99
They will undercut BT on all calls etc, and you can keep your existing emaill address if you use Outlook/OE etc
Pipex took over Homecall some time ago and it has been problem free.You get billed monthly and pay by DD.