also, traveling within the cities to different attractions and what not. trains? buses?

Your number of days per city is about right except for Paris. Paris “needs” 3, preferably 4 days. If I only had 20 days, I’d pick only 1 city in Spain and save Paris for the next trip.

I would fly from Spain to Paris or Italy. An overnight train would be my second choice if I couldn’t find a cheap flight. Within Spain, either train or bus (or maybe a flight for a long trip). Within Italy, definitely take the train. To Athens, fly or overnight ferry and, of course, ferry to the islands.

Within cities, subway and lots of walking is usually the best way to get around, except for Venice where it’s lots of walking and the vaporetto.

If you only have fours days in Spain definitely stick to one city since one of those days would be your first day in Europe. Listen to oldlady about Paris deserving more time. You could probably shave a day off of your Spanish city and add it to Paris, giving you three in Madrid or Barcelona, three in Paris. If you decide to do both Madrid and Barcelona take the train between them.

thanks, for the advice…

would you suggest booking flight tickets in advance? or buying them after we land in the country?

You’ll definitely want to book flights in advance to get the cheapest fares. You can check for cheap flights on these sites:
http://www.whichbudg…
http://www.skyscanne…

Be advised that if you fly Ryan Air into or out of Paris that the airport they use is an hour and fifteen minutes to an hour and a half outside of Paris.