Will our existing analog TV antenna work for the new digital broadcasts or should I get rid of it?

If you get good reception with your antenna now you will get slightly better after you prepare for digital. All you have to do for that is to buy a digital converter, the cost for one varies but you can order a coupon worth $40 that with another $10 to $20 dollars will all you need to spend to get ready for digital. Here is a site you can order them, you are allowed two.

Free $40 Coupons for Analog TV Converter Box