I agree you will want 4-5 hours at least. I like SFO better than LAX as well, but I haven't had experience with either post 9/11.

Last year coming back from Europe I gave us 4 hours between landing at Newark and departing on a domestic to go back home. The plane circled around Newark for an hour waiting to land. Luggage Claim was a nightmare and the customs wait was even worse. We didn't have problems in customs it was just the wait. We got through customs, rechecked our bags and then went to go wait in the security line to get to our terminal. The line was awful there as well. We ended up running to catch the plane even though it had a half hour delay boarding. I thought we would have had time to sit and grab a bite to eat but it was a complete nightmare and this was in October. January will be much worse. On top of everything they lost our luggage between Newark and Baltimore so we had to deal with that once we landed.

A few tips for customs: Dress nice! I don't care who tells you it doesn't matter. I do a lot of traveling and I have only ever had a problem when I dress casually (jeans and t-shirt). If I wear a dress or a skirt they waive me right through.

Check anything you have a question about. I've had them take mascara from me before. Throw your whole makeup bag in the checked luggage. Don't even bother with shampoo or stuff like that. It weighs down your bag and you can get it when you get here. Unless they have changed it you can't even check a lighter.

Be prepared at customs. Have your paperwork filled out and keep answers short. Smile. Where are you from, Where are you going, What is the purpose of the trip, Do you have anything to declare is what I get in most other countries. Sometimes they throw in a what is your profession or do you have a criminal record.

As far as luggage make sure you check. All of them are different. 45 lbs seems to be the norm that I get and they are strict about it. If you are 46 lbs they will either charge you for the extra weight or they just wont take it. Keep in mind that carryons space will be smaller in the domestic plane.

I hope you have a great trip. The airport stuff really sucks, but what can you do if you want to travel.