I'm sure I made lots of mistakes.

About the UL corner: White is dead and should not be able to live.

Click Here To Show Diagram Code

[go]$$B On Move 221
$$ ---------------------------------------
$$ | . . 2 . 3 . . . . . . . . . . . . . . |
$$ | 1 W . O O X . a . O . . O O O . . . . |
$$ | b X O O X X X . O . O O X X X . X . . |
$$ | . X X X X X X X X O O . O X . X X O . |
$$ | . X O O X O X O X O X O . O X X . X O |
$$ | c X O . O O O O O X . X O . . X . X . |
$$ | X O O O O X X X X X X X . O O X X O . |
$$ | . O . O X O . . . . O X X X O O X O . |
$$ | O O O X X . . . X O . . . . . X O O . |
$$ | . O X X . . . . . X O O X X X X X O . |
$$ | O X . X . . . . . X X O O O O X O . . |
$$ | X X X . . . . . X . . X O . X O O O . |
$$ | O X X . . . . X . X X X O X X X O O . |
$$ | . O X . X . X X O . X O . O . . X O . |
$$ | . O X X O X . X O X O O . O . X . X . |
$$ | . O O X O O X O . O . O . O . X . . . |
$$ | . . . O O X X . . . O . . O . . X . . |
$$ | . . . O . . . . . . . O . O . O X . . |
$$ | . . . . . . . . . . . . O . . . . . . |
$$ ---------------------------------------[/go]

After the moves 2 and 3 are miai.
Black needs 3 moves to capture white (if he needs to) and Black has more libertys then 3. But Black can also form an eye if he plays at the point 'a' next - an eye can also be formed by playing 'b' or 'c' (miai). So Black does not need to capture White at all, Black is fine after those 3 moves in the diagram.

Edit: After Move 243 you died.

Click Here To Show Diagram Code

[go]$$W At Move 234
$$ ---------------------------------------
$$ | . O X . X 1 O B . . . . . . . . . . . |
$$ | O O O O O X . X O O . . O O O O . . . |
$$ | X X O O X X X X O . O O X X X X X . . |
$$ | . X X X X X X X X O O . O X . X X O . |
$$ | . X O O X O X O X O X O . O X X . X O |
$$ | . X O . O O O O O X . X O . . X . X . |
$$ | X O O O O X X X X X X X . O O X X O . |
$$ | . O . O X O . . . . O X X X O O X O . |
$$ | O O O X X . . . X O . . . . . X O O . |
$$ | . O X X . . . . . X O O X X X X X O . |
$$ | O X . X . . . . . X X O O O O X O . . |
$$ | X X X . . . . . X . . X O . X O O O . |
$$ | O X X . . . . X . X X X O X X X O O . |
$$ | . O X . X . X X O . X O . O . . X O . |
$$ | . O X X O X . X O X O O . O . X . X . |
$$ | . O O X O O X O . O . O . O . X . . . |
$$ | . . . O O X X . . . O . . O . . X . . |
$$ | . . . O . . . . . . . O . O . O X . . |
$$ | . . . . . . . . . . . . O . . . . . . |
$$ ---------------------------------------[/go]

kills Black - here the continuation:

Click Here To Show Diagram Code

[go]$$B Continuation
$$ ---------------------------------------
$$ | . O X . X 2 . X . . . . . . . . . . . |
$$ | O O O O O X 1 X O O . . O O O O . . . |
$$ | X X O O X X X X O . O O X X X X X . . |
$$ | . X X X X X X X X O O . O X . X X O . |
$$ | . X O O X O X O X O X O . O X X . X O |
$$ | . X O . O O O O O X . X O . . X . X . |
$$ | X O O O O X X X X X X X . O O X X O . |
$$ | . O . O X O . . . . O X X X O O X O . |
$$ | O O O X X . . . X O . . . . . X O O . |
$$ | . O X X . . . . . X O O X X X X X O . |
$$ | O X . X . . . . . X X O O O O X O . . |
$$ | X X X . . . . . X . . X O . X O O O . |
$$ | O X X . . . . X . X X X O X X X O O . |
$$ | . O X . X . X X O . X O . O . . X O . |
$$ | . O X X O X . X O X O O . O . X . X . |
$$ | . O O X O O X O . O . O . O . X . . . |
$$ | . . . O O X X . . . O . . O . . X . . |
$$ | . . . O . . . . . . . O . O . O X . . |
$$ | . . . . . . . . . . . . O . . . . . . |
$$ ---------------------------------------[/go]

Edit 2: White has 2 eyes while Black only has one, it's a very short sequence

I recommend to study life&death
And take your time when reading out corner positions like that, you played way too fast at this game changing corner play, you almost lost the game on move 234

Edit 3: Another edit , I just finished going through the rest of the game and I want to ask one thing: Why did you pass on move 264? If White had just played A15 Black would be dead
Well I'm not going to say anything about the rest of the game. I can't say much about the opening, handicap is handled a bit different then an even game.

Accident I requested an undo but he didn't accept.

I'm noticing that UL corner now, I really should have been able to kill...

Move 2: This is too conservative. As black with a handicap, you have a substantial advantage early in the game. It declines, of course, as more stones are added.
Right now, with this move, you have a 7 to 1 ratio of stones. In 100 moves, you will have a ratio of 107 to 101 - almost 1 to 1. So to get the most of your extra stones, you must use them early. Attack him with something like M3 or L4.

10: This is way too cramped. Think expansively. O16 is good. P14 might be fun, though it may be thin.

12-16: Good moves. They make use of your otherwise misplaced stone at Q15.

18: Awwww......you're thinking too small here. Play Q9, and look at the entire top half of the board.

22: Good! Too many DDKs would play S6.

38: A little over-concentrated. D7 would be fine shape.

54: This leaves a gap that will cost you. Better is D12 or C11. B13 works too, but it could be tricky. ( BTW, when you have a spare move, you can kill his corner with B18 )

68: This is thin. If he didn't have D13 in place, maybe you could do it. Best here is probably F12.

74: You know that E16 can't be allowed to run. That is good. You see the problem, so why bother with half measures in solving it? Fix it permanently with F16.
This leftver problem, BTW, is what we call 'aji'. You have 'bad aji' here. F16 would remove your bad aji.

84: B8.

89: See? He has a ko threat. If you had played F16, he would not have a ko threat.

104: Why fight the ko now? How much is it worth? He can create a second eye any time with C15, so you are not fighting a ko for his life anymore. You are now fighting for a few endgame points. They may be important later, but they are trivial right now.

115: Note that he lost the ko, but is still not dead. Imagine if you had let him win the ko and played a black stone at K15. The whole center of the board starts looking like your territory.

I have to quit now...maybe more later.

_________________
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What about move 220? I'm really iterested why you played that since it took you about 30 seconds to play this, because this is called a "Half point ko" and it's "gote", not counting "dame" and plays in your own territory: it is the smallest move you can make.

I'm guessing you misread something, just try to remember that there are small kos that you don't really want to fight until the very end.
You can read about "Half point ko" here: http://senseis.xmp.net/?HalfPointKo

I believe I was under the impression I could set up some kind of snapback. Probably a misread. I was interrupted in the middle of the game once or twice as well, so I took a while to make some obvious moves.

Hi shyin, probably 95% of your problems are basic shape problems.
A few ideas:

That explains it, I know what you mean.
I really like Black 140 , you are starting to attack 2 white stones and a small group, white won't be able to save both but even if he saves them you will gain a lot from attacking them - and it's fun to keep attacking
Well you did mess up and lost a few stone but you gained most of the center so that's fine. But the most important thing that you gained is experience, you did learn that it's easier to live then to kill.

Another good move (locally) was 126, as I have shown before it kills the white corner.
It is possible that the corner is already dead but then again: "it's easier to live then to kill" and "better safe than sorry"