I can highly recommend Italy - beautiful art, architecture, scenery and music, interesting local festivals, great people and food. Beaches, mountains, lakes, the ocean, historic sites, world class museums and galleries and a lot of varied things to see and do. The best part is the wonderful Italian people. It's very easy to get out and explore Italy and further in Europe using the trains or budget flights.
Try somewhere like Mexico for great food and weather :)
But camping is a must. Hire an RV and go on a road trip!
Venice
Hawaii! Yosemite NP, both places are great! Then maybe camp at Redwood NP/SP and Avenue of the Giants.
If you stay in the US....Alaska is beautiful....especially if you take a trip in the tundra. Or head for Australia and do the Great Barrier Reef.....terrific beyond words!!!!
it would be tremendously expensive for 5 people to go to another country other than Canada maybe