Ok, first of all, these engines do NOT like cold weather very much. They're air cooled, so in cold air, they tend to not get hot enough. They rely on a pinch, literally squeezing the piston, to get compression. Get them too cold and they will sieze. If you start them while they're at room temp, and if you can get the temps up above 200 degrees or so, then yes, they'll run just fine. They'll make more power, too, seeing as you'll be able to burn more fuel per cycle.

Mine never have a problem with this, as the shell insulates them well enough to heat up and I store/prep indoors during the winter, but if yours won't, you may have to wrap a few fins on the head. I suggest cutting a sock, since aluminum foil can cause radio interference. Always leave a few exposed, and check your temps so you don't overheat it.

As for starting, here's how I do it:

While inside the house, I:

Pre-run radio check
add fuel
Check glow ignitor
prime engine
another pre-run radio check

Then I go outside and:

Start engine
Mount body
Drive

When it's time to shut down for the day, I:

Bring the car to me
Pinch the line
The exact moment the engine stops running, I pick the car up and place it on a table indoors. I then go back outside and bring the rest of my gear in
Shut down radio gear, fold antennas, park the car on a paper towel, and done.


Doing this ensures the engine is still at room temp when I try to fire it off, and I don't have to fiddle around with finding BDC when I shut down for the day, though I usually do anyways.

As for what plug to run, etc etc, I run the same plug year round. The engine, if it's being allowed/forced to warm up to full temp, isn't going to care what the outside air temp is. The conditions inside the engine will be the same when it's running in January as they are in July. My engine, by the way, absolutely loves OS #8s. Makes sense, it's an OS engine. It came with an A3, oddly enough...worked for breakin but I threw an 8 in shortly thereafter. The engine before it also loved OS 8's. The fuel I use varies, but it's always a brand name 20%N 18%O blend. Right now, Blue Thunder, but sometimes I'll run Odonnel or Byron's. To accommodate the denser air, I usually go an eigth or a quarter turn on the HSN, usually right around October or so since I run year-round, and that keeps things running well. I don't have to touch the LSN or idle screw most of the time, the HSN adjustment is more than sufficient for my engine.

These engines do not like to start when they're given a chance to cool off. If you store them in a garage or something where they can get cold, bring 'em inside for a while to warm up. The servos don't like it any more than the engine. Ideally you'll store it inside as well, I park mine on some paper towels to catch the oil drips.