Would you ever consider going second hand Rich?

At the price you're looking to spend, it might be better. MBUK have a section at the back solely for this purpose. If you see something you like, it's always a good idea to make sure you can look at it, or you're close enough to get to it.

£250.00 should be enough money to get you something fairly well specced and a decent frame. Again, at this price, avoid full suspension.

If 2nd hand isn't for you, then Michael's advice of either a Raleigh Dawes or the Flanders could be a good option.

Let us know how you get on!

Rich