Hallvard is obviously better than me when it comes to searching to internet and sent me a link that enable me to solve the crappy-flash-video-support-on-a-netbook-in-Ubuntu-9.04 problem. So, to get Flash video to work properly on your netbook in Ubuntu 9.04, do the following:

1. If you have not selected a FIrefox plugin to handle Flash yet, make sure you select the Adobe plugin from the list and go directly to step number 2 below. If you have already, like me, installed the SWF decoder version because you thought it was a good idea (it was not), move on to the next step.

2. Remove the swfdec-mozilla plugin by running the following command from a terminal:

$ apt-get remove swfdec-mozilla

On my netbook, this also removed another package, but as far as I can tell, that didn’t matter much. Then install the Adobe Flash plugin with this command:

$ apt-get install adobe-flashplugin

3. Create a configuration file in your home directory for the Flash plugin:

$ vi ~/mm.cfg

and add the line

OverrideGPUValidation=true

in the newly created file. Save by pressing :wq and then enter.

Or roughly something like that. Since i tend not to write down what I do as I go, the above guide might not be 100% accurate. Shame on me and good luck to you.