It sounds like you actually installed
matlab-support from the software center. This is NOT Matlab. This package configures a pre-existing installation of Matlab. Only install this package if you already have Matlab from MathWorks installed.
It looks like there were problems with the installation of this package. To see which process is locking the file
sudo fuser -v /var/cache/debconf/config.dat
It will result in output similar to:
root 2931 F.... frontend
The number is the process id of the process locking
config.dat. Next kill this process:
sudo kill 2931
2931 with the process id for your case. Now lets see if we can repair things:
sudo dpkg --configure -a
sudo apt-get autoremove --purge matlab-support
sudo apt-get -f install
If you are looking for a free alternative to Matlab, you should look into using
octave. The syntax and functionality is very similar to Matlab, but the GUI support is not as good.