virtualbox.org

I have a Main OS of Windows XP, and VB has Ubuntu 8.10 and im trying to make the window bigger. now when i say window, i mean how big the screen looks. I can only get it to go 800x600 max. thats not big at all. I can get it to full screen, however the actual box stays the same size. can someone help me?

Install proper guestadditions and then try to resize screen by options in Virtual box not by options in guest OS.