If my computer can't handle a million track while making songs,

can I for example record the drums alone, and the rhythm guitar alone then the lead guitar alone and mixing them togather and playing with left and right stereo stuff?
maybe programing the drums and playing bass over them
then recording the guitars (rhythm and lead) in alone
can I do this if my pc can't really handle too many tracks or that's wrong?
Absolutely fine.

Could I get some more talent in the monitors, please?

I know it sounds crazy, but try to learn to inhale your voice. www.thebelcantotechnique.com

Chris is the king of relating music things to other objects in real life.
If they're all recorded to the same tempo (via a click track or metronome), that should be fine. But you will need them playing all at once in order to mix them, unless you overdub them (record them one over another), which means you're SOL if you decide you don't like the mix later.
Tracking one instrument at a time is a valid technique, as the others have indicated.
Yep. And it's easier than you think to do it. Most DAWs have an option to either "lock" tracks or bounce them in place. Check that out for your specific daw.
Winner of the 2011 Virginia Guitar Festival

Protools HD
Lynx Aurora 16/HD192
Mojave, Sennheiser, AKG, EV etc mics
Focusrite ISA828 pres
Waves Mercury
Random Rack Gear

65 Deluxe Reverb
American Standard Strat
Taylor 712