Assuming your battery is fully charged..
What first comes to mind is crud in the fuel tank. If it had been sitting awhile, it could have developed crap in the tank, and your driving around knocked it loose.. if thats the case, it would just be a matter of time before the crud made it to the fuel lines, pump, and filters and started choking the fuel supply.
I'd pop the fuel line off the carb and point it into a large metal coffee can or other suitable container, and crank the engine over.. see if she's squirting fuel.
If you're getting a good fuel supply (and you're not runnin' 'big easy' gas) then i'd check the points, coil, rotor, cap, condenser,, the usual ignition and electrical stuff.
