Look into your x:\windows\repair directory then copy all this files to x:\windows and x:\windows\repair directorys
This is a clasical win xp service pack 2 error , some times when you install service pack2 it deletes all the 16-bit dos files
So you can just copy this files from repair directory or reinstall win xp ,install your drives and then install servis pack 2 and if you lucky 16-bit programs will work
I HAVE WIN XP BUT I MUST HAVE IT TO PLAY DOOM 3 , thief 3 , deus ex 2
x - your drive letter