The culture isn't that different from the US. In fact, other than the UK, the culture is the most similar to the US of the different European countries I've visited. There's one big difference, however: sexism. The French men gawk at pretty ladies openly, to the point of being offensive, and they'll flirt relentlessly. And grossly.

I've learned a bit of French by listening to French language tapes (well, MP3s on my iPod) and it does help to be able to greet people and order food in French. For the most part, you can get by with English as long as you're in the touristy areas and you stick to the bigger restaurants. If you're trying to order a crepe from a street vendor, be prepared to do some pointing and miming to get your order across.

Don't tip in Paris--service is always built into the bill. While wait staff in the US depend on tips, wait staff in Paris actually make an upper-middle-class income. Really, you don't need to give them anything extra.

Don't even think about taking a taxi. It's not that taxis are cheats or hard to find--I never had a problem the times I did take a taxi. However, the subway system is extensive, easy-to-use, and clean. In fact, when choosing a hotel, pick a place near a major taxi stand. You can buy individual tickets to use the subway--I just bought a pack of ten tickets (you use one ticket each time you enter a train station, and you don't use a ticket when you transfer). I used the Tube Paris iPhone app to help route me, and it worked great.

I stayed at the Holiday Inn Bastille, which was super cheap (for Paris) at $250/night. Even so, it wasn't a good value. It was next to a "Sex Shoppe" and hookers hung outside the hotel at night. It was a quick walk to the major train station Gar De Lyon, which is convenient. However, it was something like 18 stops to get to the Eiffel tower, because it's on the outskirts of the city. However, the Gar De Lyon area has a ton of restaurants around. If I had it to do over again, I'd pay the $500/night to be closer to the center of the city, but overall, the location wasn't too bad. Maybe find a hotel in the same area but not next to the sex shop.

Here's what you must do in Paris (according to me):