I've only just started evaluating hands on here so I'd appreciate feedback on my feedback [img]/images/graemlins/wink.gif[/img]

First of all what buyin is it? This is important.

Preflop, well you should be folding AJo UTG, and definately folding it to a raise. With four players on the flop it is likely you will not have the best hand.

On the flop again you should be folding with three diamonds out, as you are finished if anyone has two diamonds with four opponents. Even if a fourth diamond falls it is likely you will be beaten. CO doesn't worry me too much as he seems to be continuing from his preflop raising. Two other callers suggests someone else has the flush.
With so many people carrying on at this stage it is likely you are going to be allin anyway.

The jack gives you the added problems of the straight, and the only situation you look like surviving here is AQ.

Far too many hands will beat you here, you are just walking into further trouble. Throw this as early as possible.