Borderless windowed fullscreen.
The only reason to go old school fullscreen is demanding 3d graphics, and even those games run in borderless fullscreen nowadays. It is just not necessary nor nice for multitasking operating system to have exclusive Fullscreen by switching resolution.
Some engines like old renpy screw up on Desktop zoom. Resizing the window works fine, but if you use the fullscreen option, it incorrectly zooms by 150% or whatever your Desktop zoom is.
3rd or 1st person depends on a lot of factors. If done right, both work. iirc skyrim would just scroll the view in till first and out till third. But other 3rd have the character walking more to the left side .
