i find if your dsl sucks balls just give up and get virgin.. my friends changed from sky to bt to bla bla bla, all slowwwwww and through the standard w&nk phonelines from before the war..
our virgin media/ntl is flat out and always has been since getting it 7 years ago or so..
tell sky there not delivering you with the connection and speeds you expected and therefore they are breaking the deal... then tell them to cut you off before you call for legal advice
edit, like penfold said
really should post quicker and not wonder off