Thanks for all the ideas, me and my OH sat down and scoured lots of food sites yesterday and finally decided on:
Starters: Caeser salad, leek and potato soup or chicken skewers with dips
Mains: Rump of lamb, baby potatoes, seasonal veg and minted gravy or Roast chicken, roasted potatoes, seasonal veg and gravy (everyone loves a cooked dinner so easiest choice)
Desserts: Lemon tart with creme fraise, strawberry cheesecake or chocolate ganache with vanilla ice cream (which are the desserts already on their menu)
Have also asked what they can offer for children so hopefully they can arrange all of this for me :)