My '99 Corvette convertible has 14,000 miles on it, but the spark plugs are original. Should I be changing the plugs and if so what plugs work best?

You should be able to get 30,000 miles on the plugs, but since they have ben in there all this time, doesn't hurt to change them. Just go to the parts store and get what it calls for.

Make sure you find out what the spark plug gap is and to make sure it is set correctly.

14,000 miles? I wouldn't worry about it. The plugs will be fine till at least 30,000 miles and if they are platinum plugs they are good till 100,000 miles. When I had my 2006 C6 Corvette I pulled the plugs at 20,000 miles to change the exhaust manifolds and they looked like new, and the car sat in the garage much of it's life. Also the plugs were very easy to remove.

nice, low miles- and a nice car- but it is the age of that car that tells me it needs a major service- you popped for the price of the car, now find a really good mechanic and pop for the price of the 15,000 mile service- YOU should not even be opening the hood on that beast-