Don't see how a landlord could object to you putting a phone line in the house - it's you who'd be paying for it, not him/her, Then there's this....
O2* charges £9.50/mth for basic line rental, which comes with free evening and weekend calls to numbers beginning 01, 02 and 03 (for the first 60 mins - hang up and redial to avoid charges).
Elsewhere, call charges are reasonable if not earth shattering, with daytime local calls at 4.5p/min, calls to mobiles at 12p/min daytime, 7p evenings, and 9p connection fee on calls that aren't inclusive. It also allows you to use override providers.
Broadband:
You get 8Mbps with no download limit, and and a home phone line with free evening and weekend calls. O2's won 'best broadband provider' for 3 years running, so it comes with a good pedigree and excellent customer feedback. Its home phone's new though, so it's a bit of an unknown entity.