When choosing accomodation, self catering apartments or houses can be fantastic with younger kids, particularly if you will be visiting a city. Self catering accomodation allows you to have your own space, cook your meals and put the kids to bed in their own rooms while you stay up without having to tip toe around in the dark!
If you decide to stay in a hotel, you will find that almost all European hotels will all have cots and high chairs and you will be able to find kids menus and high chairs in most restaurants. There are also plenty of hotels which are focused specifically on families and plenty of activities which will appeal to kids of all ages. For example, in Austria and Germany you will find Kinder Hotels, which specifically cater to parents with babies and toddlers. These hotels have baby food, formula, creches, crawling rooms, activities for younger kids and some even have midwives on staff.
Other great options include camp sites in France and Italy which offer baby friendly mobile homes, rural retreats with baby and toddler friendly apartments and play areas and resorts which cater specifically to families. If you are travelling on a budget, many European hostels also have family rooms.