Hi Julie, welcome to the forums.
I personaly dont know what kind of bike a "Scott Sonoma" is. However, from what i have read in your post, it looks like a hard tail mountain bike would be your best choice if you want to do both on and off road cycling, and maybe touring.
When you go on a longer road tour, or any multi-day trip, you could easyly add semi-slick tires for less resistance, and more speed & paniers for your gear.
I hope this helps, I'll try to fallow up later with some more information for ya.
Anyone else have anything to say? This isnt my specialty ;)
buy a locally popular bike
I have biked and lived in foreign countries and have found that the best bet is to get a bike that is popular locally.
There are several reasons:
First is maintanance. If your bike is common, you will find it easier to get your bike repaired even at the local little bike shop or garage mechanic or even borrow parts from friendly local people.
Second, locals generally know what bike is best for the local terrain and riding conditions. This is especially true in counrties with rich bike cultures like Europe, China, and Japan.
The one exception to this rule is the USA where, for some strange reason, the most popular bike is a cheap mountain bike which is "huff and puffed" almost exclusively on paved roads.
Have a ball biking in Europe. Bicycling is magnificent there. Try bicycling in France/Germany along the Rhine river. There is a "bikes only" road which goes along the entire river (on both France and Germany sides of the River) and brings your through charming small towns.
Biking in Netherlands & Belgium
We spent 2 weeks biking in the Netherlands on bikes rented from the campground we stayed at. We rented a Treker hut (a well furnished garden shed). The bikes were roadsters, single speed with coaster brakes and full fenders. I can't remember the brand, but they were the standard bike in the Bergen op Zoom area. They work fine. These countries are flat, you don't need any extra gears. Also, since these were the standard bike, there wasn't much to interest a thief. Have a great time!