Replying to NEED HELP FOR VACATION PLAN!!!

so me and a couple of friends just decided that we want to go on a trip out to colorado for a week during christmas break.  We will have to figure out transportation because we arent old enough for a rental car.  Basically, we need to know the best mountain to go to that has fairly inexpensive hotels/motels and would have shuttles/buses that could take us back and fourth between the hotel and mountain.  Very good park would also be in the criteria, but i'm sure any park out west is gonna beat the east.  anyway, please help, +++++k