When that link I gave you was created I tried it and typed in the wrong number and of course I had to type the number like you have to.
I suggest you you read that link and do as it suggests
When you type (or copy and paste) the command it will list all the video modes your system supports, just change the entry in grub.conf to the one you want the default is vga=791
Try a few different ones to see what the difference is and best suits your needs
Desktop ASUS M2N-MX SE Plus, AMD 64 X2 Dual Core 5200, 4 Gb RAM, GeForce 9500 1GB
Notebook HP CQ61-311AX, AMD CPU M320, 4 Gb RAM, Radeon HD 4300 512 MB
Wireless AR9285, Audio ATI SBx00 (IDT 92hd75B2x5)
Some mistakes are too much fun to only make once!