Ashley,
If you're using Sky, NTL or Telewest you're best off with XMLTV cos Bleb doesn't get all the channels, otherwise for terrestrial Bleb is fine. I don't think anywhere has four weeks of listings!! The most you can get is two weeks. If you search the forums, I've given a detailed explanation of how to set up XMLTV correctly with all the Sky channels before and I'm sure other people have as well. If you read the XMLTV help docs it explains clearly how to choose your channels.
josh