I can highly recommend this guide in the Dorling Kindersley Eyewitness Top 10 Guides series. Not least because I was personally involved (in my own small way!) in the preparation of the guide.
The guide contains dozens of Top 10 lists for Corfu and the Ionian Islands - whether you have plenty of money or are on a limited budget. From the Top 10 bays and beaches to the Top 10 myths & legends, picture postcard villages and outdoor activities. To save you time and money, there is even a list of the Top 10 Things to Avoid.
The guide is up to the usual excellent standards of all Dorling Kindersley publications and I suggest you obtain a copy before you visit Corfu and / or the other islands.