We almost always choose paperbacks and usually not one that's been read before, and yes that has resulted in a couple of turkeys but that's part of the fun!
As we meet in our homes, whoever is hosting will have chosen the book about two months ahead.
Many paperbacks have 'Book club' questions for discussion at the back, or you can Google some, so you can print off and issue them on the night, just to get the conversation going. So everyone gets the chance to say something you could start off by giving a few of your own opinions and then go around the group.
For the first book I would choose say something that won a prize/shortlisted last year so it will be easy to get and in paperback. As you're the instigator gilly you could host the first one, by choosing the book and organising biscuits, etc. The next person does the same, that way there is some responsibility on each person eventually, and you don't get lumbered with it all!
We give a mark out of 10 (and boy do the marks vary!)