In my Humble Opinion the three best hand guns for self defense are the;
1911 Colt, and it isn't a double action it is a single action, recoil operated semi automatic,
8 round capacity, 230 gr. bullit at 850fp/s. 430ft. lb.
The P-35 High Power, single action, recoil operated semi automatic, in 9mm it is a 13 shot, 124gr bullit, at 1100 fp/s.
and my preference in the High Power is the .40 S&W, which has a 11 round capacity, 165gr, bullit at 1,150 ft/s (350 m/s)
484 ft·lbf (656 J)
The 1873, Colt revolver, in one of the fighting calibers, 38-40, 44-40, 45 Colt.
My preference is in the .45 Colt, 255 gr (16.5 g) Lead SWC 961 ft/s (293 m/s) 523 ft·lbf (709 J )
I never fell under armed carrying this in my belt.
The actual combat rang hand guns are intended for it 50 yards, and if you can't keep all of your rounds in a 10 inch circle at 50, your a dammed poor shot.
But for actual defense use, to be legal 7 yards is the standard, if he is with in 7 yards and armed and showing aggression, he is a danger to you, and your life.
The .44 mag. and bigger, are hunting pistols, they have far to much recoil to be effective defense guns, and the juries will look askance at you for using one.
To effectively use guns of this power, you need to be a experienced shooter, and use to recoil.
The grip on a Desert Eagle is like trying to hold on to a 2x4, and you need a big hand to grip it.