Well, I live in a small fishing port on the east coast of England and we have the best fish (always haddock, never cod) and chips in the UK here - everyone I know who has visited agrees! However, I probably eat fish and chips just a dozen times a year. Indian food, on the other hand - I have probably 50+ curries a year and it really is our new national dish!
You can get decent Chinese (almost exclusively Cantonese, actually) food around here although much of it is anglicised. I quite enjoy cooking Chinese food myself and have a few cook books containing recipes you'd never find in a Chinese restaurant where I live. Things may be different in cities.
In other terms my small town is limited in types of food available - there is a reasonable Thai restaurant, a good Cypriot restaurant (and takeaway for those late nights!) and one or two other more expensive haute cuisine style places but (to my knowledge) no Mexican restaurants around. For really high-end stuff, I think the nearest Michelin-starred restaurant is about 20-odd miles from where I live.
Personally, I started experimenting with cooking about 5 or 6 years ago and since then it has become very 'trendy' - Jamie Oliver and other celebrity chefs such as Gordon Ramsay have pushed good food forward into the public consciousness. The range and quality of foods available in Supermarkets has improved immensely in recent years due to this popularity although there is still some way to go before there is the same kind of range as you'd find in some foreign supermarkets. However, Mexican, Thai, Indian and Italian ingredients are widely available these days. There also seems to be a certain renaissance in more traditional English foods - I live close to the countryside and can get some excellent foodstuffs from some local butchers (cured meats etc) which supermarkets don't sell.
Unfortunately, these improvements in diet haven't yet filtered their way down to the poorer families who still eat the trashy processed convenience foods and there is still a preponderence of McDonalds and low-end pizza places which, generally, serve crappy food.
Overall though, things have improved a great deal and hopefully the range and quality of food will continue to rise in the future.