If you go for a book that claims to explain basic philosophy, there's a good chance you'll end up with complete bullshit. If I were you I'd get a rough timetable of philosophical thought, Ancient Greece to maybe around 1970, and then start reading Wiki articles - they're very good a lot of the time, and pay a lot of attention to cross-referencing.
Three bits of advice:
- Restrict yourself to Western philosophy. Eastern philosophy may be all hip and mystical and exotic and shit, but trust me on this. 19th century German philosophy digested most of what they had to offer and put it into a Western context; Schopenhauer is especially notable in this regard.
- Don't get too hung up on Scepticism or Utilitarianism. They're both simple, appealing, and somewhat elegant ideas, but lots of people just stop there and refuse to think any further, thinking this is what philosophy is all about. It's not.
- Be careful about Nietzsche. He's easily misunderstood, misrepresented most of the time, and hard to spell.
E: Dwarfy, Kant has a very clear way of writing! You just have to keep in mind that he's writing in Latin, but using German words. His phrases aren't needlessly complicated, they're as simple as they can be for the level of precision that is intended. If you want an example of unintelligible rambling, go for Hegel.
EE: Also restricting yourself to English philosophers makes you prone to a certain... flatness. The analytical school was a reaction to the Hegelei of the German Idealists, and a completely necessary one, but there's great value to be found in other traditions.