King once said John Coffey was a character modeled after Jesus Christ. Dolores from Dolores Claiborne means 'sorrow' or 'suffering' but that might be coincidence. I think the surname Creed (Pet Sematary) was chosen because of its meaning- a faith or religious belief, especially Christian. It's interesting to note that Jud could be short for 'Judge', a god-like character who interferes with or instigates important events in the story. Some of these are conjecture, mind you. Welcome!
Dolores is plural in Spanish for Dolor, meaning sorrow or pain, indeed. SK refers more often to Spanish words (in Gingerbread Girl for example), so it might be no coincidence.
Creed is not so subtle though. It can be seen as directly referring to the themes of the novel as a whole. I wonder if it would bother me as too obvious if it had been the same use of the word in my language.
Sometimes the names can even be a mix of having meaning and not. Richard Bachman's first name was from Donald Westlake's pseudonym Richard Stark (the last name was used in Dark Half of course), while the last name was from Bachman-Turner Overdrive, which King just happened to listen to at that moment, so it's rather random.
Westlake actually even has the same middle name as King, Edwin.