so, nrpe is just a method of communication between hosts. so, on your nagios box, the nagios process runs check_nrpe -H x.x.x.x -c check_c_partition
then on your host, NRPE is listening (whether in daemon/standalone mode, or on linux through xinetd). It communicates securely in response, says "oh you want me to run check_c_partition...well according to my configs, i'm supposed to run this script", so it runs whatever script you have defined and returns the output and return code to your nagios box.
So, all nrpe does is let you run scripts on a remote machine.
So, all you have to do to make new checks is write your own script that exits with a 0 (OK), or 1 (WARNING), or a 2 (CRITICAL) along with a message, then point to that script in your nrpe.cfg.
I'm not sure if NSC++ lets you define your own commands, but if it does, you could point to your batch scripts/VBscripts/python. If i were you, i'd learn some python so that you can better monitor your windows boxes.
If NRPE will build on it, then you can use it. Otherwise you'll have to use other methods, like check_by_ssh which will log into a box via ssh and run a command and return the output.