System temps are always measured in Celsius. As HVM noted there are a few applications which will allow you to see temps in F but there's really no point since the best reason to check temps is comparison (factory spec, other people, evaluating cooling products, etc) and all of that information is published in C. Do yourself the favor of thinking of hardware temps in C or you will constantly have to convert back & forth to communicate with the rest of the world.

If just for kicks you want to know what a temp is relative to another F measurement you can plug it into google for a quick one-off answer. "30c to f" for example (and the reverse works as well).

That depends on what that temp is for and what kind of cooling is being used but for a stock mid range CPU at idle with air cooling that would be a good temp.

If you tell us about your system and whether that is an idle or load temp plus your ambient room temperature we could tell you more confidently.