My old 1.6 driver throttle used to stick too. More often than not, the throttle butterfly on the carb would dry up and become stiff. A bit of WD40 sorts it out.
Carb freeze also used to get me whenever the air turned cold, but it was easily sorted. There is (or should be) a pipe that comes up from the exhaust manifold which carries heat to the airbox. If you have the standard airbox, check the hose is intact. You may also need to check the vacuum hoses to make sure the flap opens when its cold to let the heat to the carb. If you have a K&N bolt-on filter, get some of that aluminium heater pipe from halfords (or any good spares store...) and connect it to the heat outlet and tie it up so that the other end rests against the carb and the filter. Point it somewhere else in the summer.
I like carbs...they're so simple...once you've had a carb car for a while, you almost always know whats wrong with it!
