I'm not sure if I understand what your issue is but if I am correctly understanding, what I would try is setting up a virtual desktop in Wine. You can do this by running winecfg in a terminal to open Wine's configuration application, add GTA 2's executable to the applications tab, select it so that you are only changing settings for GTA 2 and not everything, then go to the graphics tab, select emulate a virtual desktop and set the desktop size to the resolution you want.