As you don't have Schottky diodes for the input clamping, use 2x 1N4148, but add an extra 10K resistor between the junction of the two diodes and the RST input pin.
Although the switch was drawn in the sim as two individual NO and NC halves (because LTspice doesn't come with a SPDT switch component), in real life it *MUST* be a single break-before-make SPDT switch (or one pole of a DPDT switch), so there is absolutely no possibility of both sides being on at the same time, even momentarily. If it did it would short the charged capacitor, damaging the switch and loosing the RST pulse. You've found a suitable SPDT switch, so just use it, COM towards the RST pin.
If you are unlucky, 4V is too high a threshold voltage, as there isn't much margin between that and the lower limit of your nom. 5V supply voltage, so the MOSFET channel may not enhance enough to pass the motor current. However, odds are its quite a bit lower, so its worth trying the IRFZ44N at 4.5V, source to ground, gate strapped to +4.5V, your motor between its drain and +4.5V, and check the voltage drop drain to source across the MOSFET. It should be under 0.1V with the motor running normally, which means you can use that MOSFET. If its higher, switch off immediately, before the MOSFET overheats.