You just installed ubuntu and noticed that you couldn’t flv, avi, wmv or DVD movies. Well ! That’s the first time only because these codecs are to be installed manually.
Here is the way you can install them.
Click the link above, It depends on the system you are using for GUI, if it is the KDE you may want to install kubuntu otherwise xubuntu version.
This will automatically install the codecs and all you need is restart of the system. Restart just to make sure everything goes fine. Then you can play most of the audio/video formats.
References : https://help.ubuntu.com/community/RestrictedFormats
Have funs now you can watch new DVD movies in ubuntu.