Dylan;

As other poster have already mentioned, choke should be working well...and it sounds like your fast idle could be raised some. See also: http://www.sw-em.com/checkchoke.htm

"The car cranked slowly... making me think the battery could be dying" is insufficient info....

...what is certain is that, your starter needs to turn over the car fast enough and long enough (if necessary, if you don't get an immediate start)...this means you need a fully charged battery (good battery itself, good charging system and all connections in between - from a snug belt to all the connections involved, from the obvious fat battery cable to the lowly and not so obvious ground strap hopping from the chassis to the engine). A pre-winter preventative tune-up certainly couldn't hurt either.

My advice: Check and adjust your choke, then do load and charge tests on battery to determine if it is the battery itself, or the vehicle which has the eletrical issues...then make whatever is deficient right so your car will serve you reliably in the cold season as it surely can...

Cheers