And that could be too, since I've never owned the HHR when it was very cold... I bought it in February, but we had an early spring...

 

If you are running the correct oil, IE: 5W-30 or even 0W-30, there should be virtually no wait for oil to get to the top end. Noisy lifters, or followers are not the norm, even in cold weather. Any unusual noise or sound is trying to tell you something about the state of the engine, which may or may not be serious. In your case, it could be as simple, as it has just been sitting for a long time, and will resolve, with that 'gentle' test drive. Until you do that, everyone is just guessing at the problem.