Suggestions for laptop?

Looking for a laptop to replace my desktop with a budget of no more than $500. I do mostly internet and word processing, very few games, like Spider and Cubis and some children's games. We do some photos, but not a lot so far. It needs to be tough, as I am a born klutz. It needs to be reliable to last for several years. Its "home" is going to be my desk, but the room where it's located doesn't have good heating or air, so the laptop will be moving around a good bit according to whether or not that room is comfortable, which means good battery life. I need a decent-sized keyboard to fit my fingers on and a well-lit screen. It definitely should have a disk drive/burner. I am a stay-at-home mom for the moment, planning to return to work soon, but I don't anticipate needing to use this laptop for work, if that helps.

This may sound silly, but I honestly don't know the answer: do all laptops these days do wi-fi or is that something I need to check on when I am looking?

The computer I have now is pretty "old" in computer terms. We are planning to keep it for my son's games and such, but I spend a lot of time calling it "you stupid machine" and getting frustrated with it when I need to do my stuff. I'm about ready for a new and better one.

Whatever advice you can give will be helpful and appreciated. Thanks!