During this rant, you do not state WHY you wanted to leave BT and/or what you proposed to replace your broadband service with.
Indian Call Centres are an abomination and should be stamped out - PERIOD. They do nothing for the customer and simply save the company concerned money so read this use as CORPORATE GREED.
Your principal problem is that you have contradicted yourself and I don't think that YOU have a leg to stand upon. You cancelled your contract and then accepted the new one, then you decided against it and when you tried to use the 'cool off' period (which I am not sure applies here) and didn't get anywhere, you took unilateral decisions against the Ts and Cs of your contract. Every time I have dealt with BT on behalf of a client, they insist on speaking to that client, and I find it hard to believe that any material change could be applied to a third party's account without their consent UNLESS she has previously given consent for you to act on her behalf. In this case, she is deemed to have been party to your contract.
By all means take this to OFCOM once you have gone through due process (by this you need to place your complaint in writing and send it to the customer complaints department). OFCOM won't touch your case until you prove that you have exhausted all other options, and even then, they are about as useless as other government quangos.
For what it's worth, I believe that YOU are in the wrong and you need to take stock of how you got into this mess before apportioning blame.
(I now await the usual slagging off for being honest and open with someone).
SHARK!