your "text mode" is using a resolution not natively supported by your laptop LCD, so the screen show it this way. Have you updated the kernel recently or changed some boot option?
You could fix it setting the correct resolution as vga option in your boot loader configuration. As example, if you would like to use "1024x768" and that your boot loader is lilo, you would need to add the line "vga=791" (and then to type "lilo" to write it back to MBR).
Alternatively, you could also search in your BIOS, some laptop have a "stretch" option, mean it "ajust" the resolution so it fills all the screen. It gives horrible fonts but if this only happens in text mode I don't think it would matter (and it's easier than messing with boot loader).