Now this is a question I feel qualified to answer! Lived in Estes Park from 1980 to 2010. Then moved to Buena Vista. Began visiting EP in 1969. Started RVing in and out of EP in 2003 and still do from BV.
Since this is your first MH experience I won't tell you about some of the back ways in to Estes Park via Trail Ridge Road.
The route I travel to this day in and out of EP from BV is US 24 to Leadville Colorado 119 to Breckenridge (I-70). You do not want to take US 24 to Minturn. That route is no fun besides then you have then go over Vail Pass which I hate.
My alternative route is US 24 to Leadville and Colorado 119 to I70 does take you over Freemont Pass which is short and pretty much a yawner.
Take I70 to I470 to US 6 (Golden) and Colorado 93 to Boulder and catch US 36 to EP. The only caveat to this route is DON'T HIT BOULDER DURING MORNING OR AFTERNOON RUSH. Mid day traffic in Boulder is not a real problem.
Now, if you are very comfortable driving your MH by the time you hit I70, I would exit I70 at Central City Parkway. Then take Colorado 119 to Nederland, and take Colorado 72 to Colorado 7 to Estes Park. This is the most scenic way in. Colorado 72 and 7 offer spectacular views of the Indian Peaks. It is somewhat twisty and up and down. You get stuck behind RVs, lot of old hippies driving old Subarus, overloaded pickup hauling wood and every imaginable conveyance. It is slower than taking the Boulder route but worth the effort for a first timer to the area.
PM me if you have additional questions.