The eeePC is very well done in my opinion - you can surf, watch movies, listen to music, use a webcam and got network via wlan - all nicely configured and ready to use. Browser plugins (Firefox) are installed as you're used to install them: Click on "install now" and that's it.
BUT: The eeePC is a really lightweight and small computer - it's more a thing to carry around, to have a mobile webbrowser and to check your mail while being elsewhere.
It just not a fully fledged PC or even Notebook, bear that in mind.
I have an eeePC as an addition to carry around, to sit in a cafe and to write some code and things like that - but watching a movie is really no joy on that kind of small display.
On the other hand: it's still bigger than a cell phone with camera and mp3 player included.
Nowadays are most open source apps even more easy to install, because usally you just grab a distributor's package and say "install this" and that's it.