Tips on getting better? (gameplay vid)

So I got a rather mediocre game of CTF earlier, and I was hoping some of you more experienced players could comment on it to let me know what I did right, what I did wrong (almost everything? haha), and any other generic tips you might have. I chose this game in particular because there were under 10 people, so I had a chance to get some breathing room and move about the map easier, because when the server is full, it can get a bit hectic trying to flank.

Also, I figured it would be nice to add another post to this subreddit, try to get some life back into it.

Part 1, 7:32 - Part 2, 6:44

Keep in mind that my pc sucks, and when I record the .avi it's only at 25-26 FPS, but when I play it's at 55-60 FPS, so it looks sort of choppy at some parts, especially when I'm typing (my text will show up 1-2 seconds later than it really did). Also, most of the times that I completely stop and stand still, I'm doing something out of game. So yeah, any comments are appreciated, unless they're just "you suck," because it's pointless to state the obvious and adds nothing.