Depends which area you are in. If you head up to Camden then the Camden Lock is a great little pub, fantastic food (The sunday roasts are amazing) and good beer. The Hawley Arms is up there, too, great atmosphere in that pub. Apparently that's where Amy Winehouse used to frequent before she... y'know... killed herself.
If you are more central, Oxford Circus/Soho kind of ends, then maybe The White Horse or The John Snow? The Museum Tavern is right next to the British Museum and it's pretty nice in there. The Sun and 13 is another great pub, across the road from Alphabet which is a great bar right in the middle of Soho, though a little bit pricey if you want to start drinking tequila. Most of the pubs in soho are pretty good, it's very competitive around there. You can probably walk into just about anywhere and you will be fine. And if not then just walk across the street to the next pub. If you find a Sam Smith then they will sell you a pint for £3, which is pretty good these days. Wouldn't recommend the vodka though, it gives pretty brutal hangovers.
If you head down to Brixton (Dunno why you would, but you never know) then the Electric Ballroom is a tidy little bar with good beer, dunno what the food is like but it looks nice at least. Grand Union is just down the road as well, they have a really nice outdoor area which is all Thai beach huts with heat lamps in them.
The Assembly House is pretty great, up in Kentish Town, that's where they host Barcraft during GSL/MLG weekends. Uh.... Bonds, over on Bond Street is OK though it tends to fill up with bidniss men after 5. TBH unless I know what sort of area you are going to be in then most of this information probably isn't going to be of any use. London is pretty big, dude!
Log in to comment