Please use the installer instead of the zip and allow it to download and install the base graphics (and sound and music).
Otherwise reading the enclosed readme would have been helpful.
my firewall settings means when i use the installer it wont install right and im using my university internet so firewall settings can't be altered
as to the read me for help
Before you run OpenTTD, you need to put the game's data files into a data/
directory which can be located in various places addressed in the following
For OpenTTD you need to acquire some third party data files. For this you have
the choice of using the original Transport Tycoon Deluxe data files or a set
of free data files.
Do NOT copy files included with OpenTTD into "shared" directories (explained in
the following sections) as sooner or later you will run into graphical glitches
when using other versions of the game.
this doesn't really help either.