Sorry to state the obvious, but you need to pick a street that's close enough to the attractions but far enough away to be quiet. The streets north of Dulwich Park between Lordship Lane and Dulwich Village are perfect for this (Woodwarde,Beauval Rd etc). Almost rurally quiet but 5 mins walk from ED bars and shops, 3 mins from the park and 5 from the village. The only problem is that they are full of golf jumpers, sunday morning car washers and retired headmasters.