It is strange that grub has graphic problems already (I am talking about the boot menu). Do you get a DOS-like blue text menu instead of the animated SUSE logo screen? In this case, there may be something wrong with the bootloader installation. Maybe grub doesn't find the file with all the graphics (/boot/message).
But if grub shows up OK and the boot process is just text based, it's easier:
Check /boot/grub/menu.lst (root!) for the line that loads the kernel. Two paramters control the appearence: vga= and splash=. vga= controls the screen resolution. Pick a suitable value from the table below.
| 640x480 800x600 1024x768 1280x1024
256 | 0x301 0x303 0x305 0x307
32k | 0x310 0x313 0x316 0x319
64k | 0x311 0x314 0x317 0x31A
16M | 0x312 0x315 0x318 0x31B
The splash= parameter controls the behavoir of the splash screen. Choose between splash=off/verbose/silent. In 'silent' mode, no text messages but a progress bar will be shown. 'Verbose' shows text on a graphical background and 'off' shows just the text.
If you have changed the vga= parameter, run (as root) 'mkinitrd' from command-line. This will ensure that a splash screen of the correct resolution is available at bootup.