Sara, good news is that the metric doesn't ride Mt George so I would say it's a good route for a beginner IF you can handle long climbs and a few somewhat steep and winding descents. The stretch from the start to Fairfield is a serious of little gradually steepening rollers, then Fairfield to Mankas Corner is a lovely flat ride, just a tiny bit up hill. Wooden Valley Road starts climbing with a series of rollers. You need to be able to anticipate shifting and make sure you don't burn out your legs on these little rollers because you have a long climb immediately in front of you. CA-121 is one long steady climb for someone who hasn't really tested themselves on hills and then there are steepish sweeping turns into Moskowite that would be good to learn on as long as you can hold your line. Since this is a group ride, you need to be sure you won't swing into someone's path (says SK after nearly plowing into someone yesterday). Out of Moskowite, you've got a long false flat - several miles of 2-5% grade. It's a gorgeous area but it can be freakin' hot on a May afternoon - start early. You'll have a mile or so climb up the back side of Cardiac along the lake and then a fast and swoopy downhill past the dam and down the Canyon to Lake Solano (maybe 10 miles). From Lake Solano, you'll have a crappy very short and steep hill (very short, I just like to whine because it's so short you think you can stomp over it but it's just a tad too long and steep for that). Then you'll have a beautiful cruise along Pleasant's Valley Road. It's another false flat climb of about 5 miles then a fun gradual downhill run into Vacaville.

The organizers call it a beginner ride, but it is really a ride for fit or very determined beginners. Only 2,800 ft of climbing but the climbs are long and the descents steep with turns requiring good skills. 2,800 ft of climbing doesn't seem like much, but I think it is harder climbs that the 4,500 we had yesterday in San Luis Obispo (given the same temps).

Other flatter options are the Delta Century in Stockton (totally flat) this weekend and the Lodi Sunrise Century on 5/19. I don't want to discourage you from the Monticello Ride but you need to know the route has long climbs and it can be hot. I have no clue how well the ride is supported either, which is a critical thing when you're new to managing your water and food intake. If you're going to tackle the ride, at least going into it with a little knowledge about managing your resources is a good thing.