Map of the United Kingdom
For most English-speaking visitors to Europe the UK is the first, main, and sometimes only port of call. And to be fair, whether you are interested in scenery, nightlife, or history, there is plenty to keep you entertained.
The scenery in Britain is some of the most varied in the world, from Dover's hideous white cliffs, through the samey greenery of Kent and past the urban sprawl of London you might think your trip has been wasted. But there's good news! Once you get past the bleak ugly flatness of East Anglia things start to get interesting. There's some beautiful hills in the peak district, followed by moors and dales in Yorkshire. Finally you reach Scotland, and that's just fantastic - pretty towns sitting right under stunning mountains, rivers running through spectacular twisting lochs and down to the sea, where you have white sandy beaches, and ferries to the Western Isles, which are more of the same but better.
For nightlife, the UK has everything, from pubs and bars, through clubs, to cinemas, theatres and unpretentious casinos. Basically, if there's a way to meet people and entertain yourself, you can probably do it in Britain. And as an added bonus you can probably get drunk while you're there.
The history is in display in the streets as well as the museums, and in a language you can understand. For your convenience the history of lots of other countries has been appropriated over time and hidden in the British Museum. Want to see the remains of ancient Greece but can't be bothered flying to modern Greece? Have a look at Elgin's Marbles. Interested in the ancient Egyptians? Not much point in visiting Eygpt - the pyramids were all emptied and the best stuff shipped over. Even the Rosetta Stone. And that's just in London... Historic cities like Bath and York have street after street of nothing but period buildings, while the whole countryside is littered with amazing castles.
There is no point recommending the UK, because you're probably going there already, so just enjoy it.