A cut above most of the books in the Bluffer's Guides series. The cover blurb says "An amazing amount of solid fact disguised as frivolous observation", and this is actually the case. How do I know? I included a quotation from this book in an essay I did for a philosophy course at university and got a good grade. (Admittedly, the fact that I also quoted a lot of serious philosophy books may have had some bearing on the grade. I wouldn't recommend relying only on this book for a serious course!)
The author swiftly deals with common myths about philosophy and gives a quick tour of Western philosophy while making fun of the whole endeavour. It's a bit out of date now, but this only shows in the section titled "The Contemporary Scene". You’ll just have to bluff your way out of your lack of knowledge of the contemporary scene.
If you enjoy this book and want more philosophy but still want it served up in an accessible way, without the logic symbols and associated jargon, you might also enjoy "Sophie's World" by Jostein Gaarder.