As a bloke with FAR too many airguns, I would tend to lean towards a .177 at sub legal limit levels. The trajectory is much flatter so it is much more forgiving to errors in range estimations and still kills rabbits/crows/pigeons etc. very effectively (I hesitate to tell you your business, but please only headshots though as neither really has the power to consistently achieve body shots).
I could write pages on scopes and rifles but a lot of it is down to personal choice and budget. Contrary to the usual advice with a normal rifle, I would advise spending most of your money on the rifle and less on the scope, especially for hunting, as the cheaper guns usually have rubbish triggers and can be rough. My recommendation for a lower end package would be a BSA Lightning XL with a Hawke 3-9*50 on top, possibly with mildots as they are quite useful for the holdover and under. You can pick them up a package for around £250ish second hand.
Other good guns that I have personal experience hunting with are the Weihrauch HW35, HW95K, HW57 and HW97K, plus I am told that the HW77 and HW80 are also excellent. Air Arms do the Prosport and the TX200K which is my current favourite air rifle and comes recommended. If you can find one the Theoben Evolution gas ram is also lovely, and a safer bet now that Impact Air have taken over the servicing and maintenance responsibilities.
Scopes to consider would be the hawke range, MTC Optics (the Taipan series are personal favourites) as well as Bushnell and Nikko Stirling. All will last forever and the optics are quite impressive for the price, especially with the MTC scopes. I do all my hunting on 6x so any scope around that range is ideal. Right, that's enough waffling for one night, I hope it helped,
Alistair