Don't want to get into a peeing match about food, no matter how entertaining that may be.
Just to say if you go to tourist and mainstream places in the UK, the food WILL be utter, utter rubbish. Lots of people visit the UK and walk in Aberdeen Angus in Leicester Square and think somehow they are eating UK food.
But there are tons of incredibly good restaurants in the UK - You need to be a bit savvy to find them and I find they are consistently better than their counterparts in France and Italy for example. This was not the case ten years ago.
As far as Indian food in U.S. - well I can only talk about New York, but I know a lot of expats living in NY, and if there is one thing they cannot get in NY, it is decent Indian food. (That is the Anglo-Indian food that is commonplace in the UK, not the Indian food that Indians eat in India). I would say a UK expat living in the states is the best judge, just as I believe my Texan friend living in London when she says that Tex Mex in the UK is not what it is in the US.
June vs August. August is more likely to be drier, sunny and hotter. Also more UK people tend to be on holiday, which means there is more of a holiday spirit at that time of the year. Of course it also makes tourist places busier which is no bad thin in my book. But peace and tranqiuility are harder to find unless you go to more remote places.
Ireland, Scotland, England etc all very nice, so whatever you choose should be cool.
