maya particle: crushing building

I uploaded this movie to youtube with settings below.

size 320x240

format FLV
video
codec On2 VP6
data rate 700k/sec
frame rate 30/sec

audio
mp3
16kbps mono

application Adobe After Effects CS3

I tried another formats and another settings but this setting was most clear.
(I also tried the size 640x480 that is recommended by yutube)
I am not satisfied with this uploaded movie because this is very noisy.

I must study more.