If you're British (a citizen of the UK since the late 70s, though I can remember being a Subject of Her Brittanic Majesty before there was such a thing as UK citizenship) you might refer to the British Isles which are the island of Great Britain and the island of Ireland, plus a quite a few small ones (Isle of Man, Western Isles, the Hebrides, etc).
However, citizens of the Republic of Ireland do not use the term British Isles, and it does not appear on their maps or in their atlases.
When the british use the word "America" they mean the USA. But in Spain, America refers to countries of the continent of South America and "America del Norte" means the USA.
To a brit, Northern America means the USA and Canada. North America though includes Mexico. And "The Americas" means the two continents of North America and South America.
But most of the time we know what we mean.
Oh, nearly forgot! No, I don't think Graham Norton is hot. And although I found his show funny at first, I went off it quite rapidly mainly because his humour mostly consists of demeaning other people.