1997 Honda Accord Axles

I am a female without car knowledge. My car is a Honda 1997 Accord 4cyl (I assume 2 wheel drive or front wheel drive; don't know the difference). I had both axles replaced in December 2007. Since then, I have put on approximately 15,000 miles on my car. When I went to mechanic for a battery matter on 7-13-10, I asked him to check out the rest of the car, too. He told me that the radiator needed to be replaced (said it was dangerous to drive as it was) and that the alternator and battery needed to be replaced for a total of 950.00 ($550 for alternator and battery; $400 for radiator). He told me he was giving me a deal. I agreed and had it done. When I went to pick up the car, I told him I was glad the car was fixed and looked forward to taking it on a trip. He said that it would be dangerous to take it on a long trip because the axles needed replacing. I told him that he just replaced them in December 2007. He told me that did not matter and that they needed to be replaced. He told me he'd give me a break and charge me $250 to replace them. He said it would be dangerous to drive with the axles as they were.

How long do axles last? I assume the alternator and battery needed to be done given age and miles of car, right? (I replaced battery almost five years ago, but never alternator). Would value your opinion. Thank you.