I�m the biggest fan of cruising and sailing. And interestingly, when you�re on a budget, need to know more or less how much you�re going to spend in advance, need everything included and can�t decide where you want to go, all answers lead to a cruise!
My favourite company is Vacations to Go. I�ve used them for years, especially in booking last minute point-to-point elements of cruises or sailings.
http://www.vacationstogo.com/
The next company I�ve seen recommended in this thread is Cruises N More. I�ve not used them, but I saw another thread where someone recommended them.
http://www.cruises-n-more.com
I would also suggest, if you�re looking for something exotic and economical that time of year, you might consider Cuba, or alternatively, hiring a small cabin cruiser through the southern French waterways. I did this two years ago and the children say it was one of the best trips we�ve ever done!
http://www.fcwl.com/
Personally, I�m not fond of travel to Spain or Portugal during many times of year, due to the number of fellow-Brits who are there, robbing us of our peace and quiet. Sadly, in places where travel is cheap and bountiful, there�s an element who have created a very bad name for the British tourist. Saddest of all is that we all tend to get covered with the same brush!
I wish you a bon voyage!
Fr Bill