How long do you rest sore muscles?

I went skiing on Friday, and it was the most intensive workout I've had since surgery. Yesterday I did nothing but hike the stairs a few times. I was sore all over (and not from falling either! )

I feel much better today but still sore (mostly calves and quads). I want to go running as I'm doing C25k to train for a 5k in March. I don't want to mess up my training schedule (I'm afraid missing a regular day will lead me to rationalize missing more), but I really don't want to hurt myself either.

What are your thoughts? Is it safe to run? Should I do some other cardio? Should I take a second day to rest?

it's hard to say, depends on how sore you are.  if it is just general soreness, you can often work through it.  typically after you workout regularly, the soreness will be less prouounced.  the trick is to not work through an injury or any really sharp pains.  it takes some time and experience to know your pains and judge what you can safely work through and when you should absolutely lay off.

 I rest 1 day usually