This really depends on the type of VESA 2.0 compliant graphic card that you have in your system, and the amount of video memory available. This is just a matter of testing which modes work best for your graphic card.
The following table shows the mode numbers you can input at the VGA prompt (actually these numbers are plus 0x200 to make it easier to refer to the table)
Colours 640x480 800x600 1024x768 1280x1024 1600x1200 --------+--------------------------------------------- 256 | 0301 0303 0305 0307 031C 32,768 | 0310 0313 0316 0319 031D 65,536 | 0311 0314 0317 031A 031E 16.8M | 0312 0315 0318 031B 031F
For convienence, here is the same table in decimal terms
Colours 640x480 800x600 1024x768 1280x1024 1600x1200 --------+--------------------------------------------- 256 | 769 771 773 775 796 32,768 | 784 787 790 793 797 65,536 | 785 788 791 794 798 16.8M | 786 789 792 795 799
[The author would be happy if you could supply him with additional 03xx numbers for additional modes i.e 1152x900?]