Your widow's pension will be paid into the UK bank / post account you wish. The Post will probably be the cheapest.
Are you already receiving your British retirement pension?
Your Swiss AHV pension will be calculated when you retire (Is it now 64 years of age) and paid out in GBP in England. I believe you should contact Newcastle pensions and they process the claim for you. Maybe you can check on this before you leave here, at your local AHV office.
I claimed for my British pension here and the Swiss informed Newcastle who now pay me here. That is the way it works in the EU now.
http://www.dwp.gov.uk/international/...contributions/