From Harry Potter and the Prisoner of AzkabanSo yes, it appears that Madam Rosemerta was running The Three Broomsticks at the time.
"Do you know, I still have trouble believing it," said Madam Rosmerta thoughtfully. "Of all the people to go over to the Dark Side, Sirius Black was the last I'd have thought... I mean, I remember him when he was a boy at Hogwarts. If you'd told me then what he was going to become, I'd have said you'd had too much mead."
"You don't know the half of it, Rosmerta," said Fudge gruffly. "The worst he did isn't widely known."
"The worst?" said Madam Rosmerta, her voice alive with curiosity, "Worse than murdering all those poor people, you mean?"
"I certainly do," said Fudge.
"I ca' believe that. What could possibly be worse?" "You say you remember him at Hogwarts, Rosmerta," murmured Professor McGonagall. "Do you remember who his-best friend was?"
"Naturally," said Madam Rosmerta, with a small laugh. "Never saw one without the other, did you? The number of times I had them in here -- ooh, they used to make me laugh. Quite the double act, Sirius Black and James Potter!"
They also serve Gillywater, I think hard cider, and butterbeer at The Three Broomsticks. I imagine there are also different kinds of ale, and although I haven't heard of Red Currant Rum (which at least sounds tasty!), I'd imagine if they're serving Firewhisky, there are probably some other kinds of hard alcohol.
I'm not entirely sure (this may be a question slightly better suited for the Being British thread), but I think in most pubs in the UK, you can buy some food.