Continental Travel Contact MTB tyres, 26" x 1.75, complete with inner tubes (Presta valves), price only applies to Reserve & Collect, otherwise full price applies (£23.99 instore, £21.56 usual web price).
£23.99 at Evans cycles and similar at others so this seems to be a good deal. These get some good reviews, bonus is the Kevlar inner that might help prevent punctures (especially when used with my slime tubes!!).
Tyre & Tube also come with a 1yr Return-to-store guarantee, should they fail prematurely.