Hey,
I bought Postal 2 Complete today off GOG, and my Menu Buttons don't show. I looked at the similar thread, and done everything there.
Set Affinity to 1 CPU (It slows down the game to normal, but the Menu Buttons are still missing)
Run in Safemode (Worked once but I changed the resolution and it's back to missing)
Updated Graphics Driver
Any help would be great.
My Specs:
Pentium E6420 Dual Core
Gigabyte 965P-DS3P Motherboard
MSI 9600GT 512mb
2GB RAM
Windows XP SP2

And just like that, I fixed it.
Just had to change the Menu resolution, aswell as the game resolution in the Postal2.ini file.