I'm with Lauren on this one -- Salida, Buena Vista, Leadville, and the upper Arkansas River Valley.  Lots to see and a variety of activities for all ages and levels.  Do a search here on Salida and you'll get a lot of info.  
If you want to do RMNP, I'd suggest Moraine Park CG in the park if you can do w/o hookups (it's cool enough not to need a/c).  While Fall River Rd. is closed this year, you can still do Trail Ridge road plus many, many hiking opportunities on the east side.  
Camping near Central City would not be near the top of my lists of places to go in CO.