Brasero works pretty good, K3B works great, but if those give you any problems and you just want a nice simple and stable CD and DVD burning app, give GnomeBaker a try.
GnomeBaker is really straight forward. Data DVD, Data CD and Audio CD are all really easy to do. You can even copy discs, erase RW discs and burn image files.
Installation is easy. Open up the Ubuntu Software Center and search for GnomeBaker and install it. There are some rumors that it has been dropped in Oneiric Ocelot 11.10 and if that is the case you will have to install it via the terminal.
Open a terminal window and type:
sudo add-apt-repository ppa:gnomebaker/stable
That will install the needed repository. Now to update and install GnomeBaker, paste this in the terminal...
sudo apt-get update && sudo apt-get install gnomebaker
Thats all! Have fun!