Hi Jimmy,
Welcome to the Artsoft forum.
Laptops are not recommended for use with Mach3 unless you plan on using an external motion controller (such as the Smooth Stepper etc.
http://warp9td.com/).
Yes, you will be able to turn on / off the mill spindle without using the software but the way in which it is done will depend on what you have (VFD etc.).
It would be best if you get everything up and working to your satisfaction, using the Demo Version (
http://www.machsupport.com/software/mach3/) before you buy the Mach3 license.
The Mach3 licence is portable between PC's and laptops etc. so you only need to buy it once.
Please take the time to read the documentation
http://www.machsupport.com/help-learning/ and perhaps watch the video's - don't worry too much about the things you don't understand yet, it will come. (I have been using Mach2 / 3 for the last 10 years and I still don't know the half of it
).
Tweakie.