hi. i'm doing what ur actually asking. just starting also on this though but its working. here the steps i took to make it appear:
first stage: vga controller
1. first design/or edit an existing vga controller file. if u r using de1 or de2, its in one of the lab demonstration file.
2. create an altpll using the megawizard for the vga timing
3. instantiate to connect vga and pll plus your color settings
2nd stage:character calling
1. once ur vga is running, create an altrom to call an .mif file or hex file. (also in the cd or u can google it. i.e tcgrom.mif)
2. in ur top level file for stage 1, instantiate the rom file and multiplex the signal for the character to appear together with all background colors u want.
i also try a number of websites to help me out on this especially on the mif usage.
hope this helps.