i will keep an eye on this thread as dh and i are in the midst of planning - he gets "long service leave" here as he has been with his company a long time - entitled to 2 months paid leave so far (and gets another month in nov 2010 or 2011 can't remember) + 4 weeks paid annual leave each year. we were supposed to go overseas this year but with the economy we put it on hold (layoffs happening etc and did not want to be away for that). so the plan is to take the kids out of school next year for May -Aug for 3 months dates depending on flight prices...so we go for the Northern summer. We will be going to England, Wales, France (ILs just retired to Brittany), Spain (BIL and his wife live there) and Italy with a possible ferry across to Morocco if i convince dh.
dh read about hiring a car in France so we will fly into Paris to start the trip - you can lease a car in France (even as a foreigner) for a great rate, drive all over europe and return it anywhere in France. They are all recent cars (no more than a few years old)
we will bring DVD player i think. we will be staying with family and friends most of the time and will mostly need to research options in Italy, Morocco and Paris (using ILs as base for rest)
mine will be older than yours but i will bring similar things that i posted on the thread Jaime linked to. i will also probably shop at markets in each country for local handmade or second hand stuff to entertain the kids and keep as souveniers. look at gift shops near/at the touristy things we visit (ie colouring book from museum in paris would be cool or kids game in spanish from stay in Spain and teach them some spanish words...)
good luck - please post back when you know more of where you are going