Ati radeon hd3200 is showing as having 256 mb of dedicated memory

If its onboard video you can change it in your BIOS and allocate as much to the gpu as you like.

can you tell me how please?
(as you may have noticed im a beginner at this  

Power on your and a splash screen will appear (award bios or something like that) at this point you want to enter setup and you do this by either pressing del key or whatever it promps you at the screen to press to enter setup.

Can you tell me some of the options that are in your bios or the motherboard you have?

Every bios is different in options.