This link will give you a list of all the broadband options available at your premises (which will be available from various suppliers), and
This link
will give you the options, and prices, if you decide to go with BT.
As others have said, your speed requirements will be minimal for your type of usage.
Since you will be moving your phone line as well, although you have to pay line rental to enable to broadband to work, you need to think about what sort of call plan you need to make sure you are not paying for something you don't need - caller display should be provided at no extra cost, but there will be many other options, including free evening and/or weekend calls, free 'anytime' calls, inclusive calls to mobiles, etc. etc.
As DanielCoffey and Goosegirl have already mentioned, when your contract ends don't roll over and pay the new price - a good idea is to find the best price for the same package from another supplier, and then ask your supplier to match it (they probably won't, but you're almost certain to save money if you persist.)