It shouldn't take anywhere close to that once you have the settings tweaked but it does still take some time. Please see here for all the Handbrake command line options: https://trac.handbrake.fr/wiki/CLIGuide
I haven't tested this but using this line instead of the one in the script by default should speed up the encoding
Set SIZE=--width 720 --height 480
Those two lines should help, but only change the resolution to this if using a compatible US NTSC TV / Monitor.