I took a look at Consumer Reports. They are a ton of very good cameras available for $300 or less.
As GB said, go for a major manufacturer and shop at the electronics stores on line.
epinions.com provides battery life in the details for the cameras they report on. In reading CR, Sony seemed to have the best battery life measured in the number of snapshots per charge.
I'd look for a 5 mega pixel (minimum) camera with a 3x optical zoom. I would also recommend getting a larger memory card to capture photos. Most cameras come with a minimal one. Look for a 256K or higher capacity so you don't have to worry about running out of storage capacity at a critical moment.
They come in several size categories - sub-compact to fit into a pocket, compact which are a little bigger than a kodak disposable camera, and larger.
"If you want to make an apple pie from scratch, you must first create the universe." -Carl Sagan