There's not much to write here except some players do better than others. It's not a RAM issue from what I've seen.
Go with players that work or go get a faster machine. However there are some folk that want Microsoft to fix their player. You can bet what MSFT's response is.
Hi, I have an IBM X31 notebook (type 2672) running windows 7 and ubuntu 10.04 netbook edition. It has 1GB of RAM, a 1.4GHz processor and 320GB HDD. When I play video on itunes on windows 7 the playback is very jerky but the audio smooth. When I then play it on VLC media player (playing a DVD) the playback and audio are both smooth. However when played in ubuntu on either VLC or the built in movie player the playback becomes completely messed up with green pixelation etc. Can anyone suggest what might fix the itunes playback, would upgrading to 2GB of RAM fix this?