Because you are a new user I wonder if you allocated the space on your
hard drive. Just because you have a large drive means nothing if the
space sits unallocated.

I use the partition editor to play with the space of my hard drive,
this editor is under >system>administration if you don't find it start
the synaptic package manager and install it.

Starting the editor will give you a picture of your hard drive and how
it is set up. If you find this is the problem then allocate some space
to play with and all will be fine.