Open Boot.ini with notepad after changing the "Read only" attribute.

Copy an existing line found underneath [operating systems] and add "/basevideo"

This will allow NT to start with minimal drivers and a standard VGA video driver.  Below is an example:

[boot loader]
timeout=5
default=multi(0)disk(0)rdisk(0)partition(1)\WINNT
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)\WINNT="Windows NT Workstation Version 4.00"

multi(0)disk(0)rdisk(0)partition(1)\WINNT="SAFE Windows NT Workstation Version 4.00" /basevideo

WARNING:  Be very careful not to change anything before "\Winnt"  this is the ARC path to your boot partition.  Changes in these values will cause your system not to boot.