Remove WGA notification

run winodws\system32\wgatray /u

Then delete

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\Notify\WgaLogon

Then delete the following in system32

wgatray.exe
wgalogon.dll
dllcache\wgatray.exe
dllcache\wgalogon.dll

And if
SoftwareDistribution\Download\6c4788c9549d437e76e1773a7639582a
exists, delete that whole dir and reboot

Play h.264 on slow computer (mplayer)

mplayer -vo xv -ao alsa -lavdopts fast=1:skiploopfilter=all video.mkv

or

mplayer -vfm ffmpeg -lavdopts lowres=0:fast:skiploopfilter=all video.mkv

I've had better success, framerate and quality with the first one.