Peterborough is a hole in my opinion, hope you guys can speak polish
If you are looking to eat in town though this is a good indian restaurant:
Bombay Brasserie
47, Broadway, Peterborough, Cambridgeshire PE1 1SQ
Tel: 01733 565606
Also, if you don't go into Peterborough there is nice pub in a village very near the showground (does nice food too), its the Wheatsheaf Inn in Alwalton