so i want a computer to do light work like some word processing, internet surfing, video streaming and most importantly audio editing (none of this will be done at the same time) this lead me to the beaglebone black its cheap and I've read that it runs ubuntu. my question is can it run audacity and will i run into any problems when it comes time to update ubuntu? the only thing i really want a computer for is to run audacity. is there anything i need to know before diving in? also if ubuntu isnt the best os considering i only need it for a limited amount of things what os would you suggest. thanks to all who help.

It seems that a regular install of Ubuntu will not work on that thing. See this from the Beaglebone website:
http://beagleboard.org/project/ubuntu/
There are some graphics problems noted there as well.
You could always contact the Beaglebone people and ask them if the system is up to running audacity on Ubuntu.
I would think that you would need a more powerful system for audio editing if you want it to perform well.