Of course this is all subjective, I've yet to make it to Vermont or Yellowstone or Alaska, so I can't comment. This kind of question requires a response from that one guy(or gal) who's been everywhere.

But if you want the opinion of someone with only a modest travel portfolio, then I'd have to agree with the California Hwy 1 touters and if we're talking mountains lakes and forests, then how about The Blue Ridge Parkway in VA and NC?

If you ever have the opportunity, check out Skyline Drive in northern Virginia. Its like driving on the edge of heaven. Beautiful, peaceful, quiet, a wonderful change of scenery.

Although it really may not compare to the scenery in other areas, I am somewhat partial to the scenic drives along the upper Mississippi River on both the MN & WI sides, especially from around LaCrosse,WI\Winona,MN area north. No mountains, but plenty of bluffs, trees, water, & prime area for bald eagle watching. Although the vistas are not there like at the Grand Canyon or other national parks, driving through a forest, down a 2 lane road in northern Wisc with all the trees towering overhead is not something you will soon forget.

A Vegas buffett with nobody in front of me!

Yellowstone's beautiful mountains are best seen in the winter. Red rock formations in the Four Corners area (NM, CO,UT & AZ)will take your breath away. Pacific Coast from Monterey CA to Seattle WA has a different look every time you turn the corner. Any of the Alaskan state parks. Where else in this fine country will you see people making an extra effort not leave a trace that someone was there before you. Oahu HI comes in second behind Alaska for it's beautiful parks. Except in HI, people are not as conscious of the tacks left behind.

Hawaii
Vermont
California
Washington