is this standard?
 

I'm in the BB w/ KQ, new to the table and check 4 handed. flop K65, 2 diamonds, i have none. I bet 2/3 pot, utg calls, stacks irrelevant. turn Td. I bet 2/3 pot again and get called. river 4d, check and fold to 1/2 bet.

Re: is this standard?
 

standard for full ring...did you mean that there were only 4 players? or that four went to the flop?

at a 4-handed table, i think that KQ is a raise.

Re: is this standard?
 

The river is by far the most important street. Obviously a read is what makes this decision one way or another. If the villain bet less than half, say 1/3 then I would call. If the villain bets the pot it looks suspicious but I think you still would need a detailed read to call.

The 1/2 pot sized bet is the perfect amount for villains flush draw, this way he milks you if you cant lay down your top pair, and doesnt check giving you the opportunity to check behind. Its most likely that the villain doesnt know what he/she is doing, but this type of bet could have come instinctivly whether the villain took time to think about the situation or not.

I would definitely lay this down without a read.