Using Quartus II without hardware?

You don't need the hardware, but you will need the hardware libraries associated with whatever FPGA etc, that you are basing your design on installed in order for Quartus II to allow you to open your project.

When you are at university next and have your quartus II design open, have a look at the top of the Heirarchy tab there will be a little yellow pyramid type symbol with something like "Cyclone II: EP2C5F256C8" next to it for example. Your copy at home will need the corresponding libraries installed to be able to open your project, in this case you would need the Cyclone II libraries.

All of these libraries should have been available when you downloaded quartus II, and can be downloaded free from the Altera Website....

and don't worry about asking stupid questions... I am still very new to VHDL and Quartus II and ask them all the time... people are generally very helpful!