I browsed Google for quite a while before I finally found a good product for recording screencasts on Ubuntu. Most software I found, no offense gtk-recordMyDesktop, was extremely outdated and hardly functional. Video quality was either terrible or video/audio was out of sync.
Enter Kazam!
Thanks to some more strict queries on Google, I found
Kazam on
AskUbuntu.com.
It has an extremely simple interface, as seen below.

The quality is just fine for simple screencasts, and it allows you to record audio that actually syncs with the video!
Installation
First, we need some Python modules to be installed.
$ sudo apt-get install --reinstall gir1.2-gtk-2.0 python-software-properties software-properties-gtk
Now we actually grab Kazam as instructed by their site.
$ sudo add-apt-repository ppa:kazam-team/stable-series
$ sudo apt-get update
$ sudo apt-get install kazam
And you're done! You can run kazam via the command line or your distro's menu.
Extras
If you happen to have FFMpeg installed, here's a nice 2-pass video/audio
encoder script that encodes with H.264.
April 25, 2012