Correct, setting it to 12 is also too large.This isn't entirely correct - when you set Terminal manually for ASCII/DOS, you can't set the right size, only very small (9) or too large (14)
but then use this in the Help:
OldDefaultFonts=0
0: Use scalable default fonts (e.g. Consolas for ANSI and ASCII and Verdana for Variable) when available
1: Use old non-scalable bitmap fonts (SYSTEM_FIXED_FONT, OEM_FIXED_FONT and SYSTEM_FONT)