Some versions of flask are upgrades that assume you already have some stuff on your computer. When you install flask do you just get a single .exe file or several files and several directories? If you only get a single file with no extra directories then your version of flask is not complete. For more general info/downloads go to: <A HREF="http://www.doom9.net" target="_new">http://www.doom9.net</A>
There are hundreds of codecs, which ones were you interested in? I installed Flask and Divx at the same time so I don't know which one installed what but between the two you should get the job done.
take lakedude's advise and visit www.doom9.net
in the software section you can find a"ripping pack" for Flask. that contains every file (Flask files and codecs and DVD ripper) you will need to run Flask properly. you will also find a guide on how to use Flask in the guide section of the website.
if you think that guide is a bit to complicated for a newby you should go to www.divx-digest.com and check the Flask guide by Nicky Page. this guide gets even the absolut newbie going.