Your router is a 54g type which offers a 54mbps wireless connection and a 100mbps wired connection.
This is perfectly normal presuming your connection is via a cable. Your wifes laptop has a 54mbps wireless adaptor and your router is also rated at 54 mbps wireless, denoted by the 'g' in 802.11g. Your connection must be via cable, which in your case (and in general) is faster than wireless, usually rated at 100mbps. It's a strange concept to anyone unaware to think that you connect at two different speeds to the same router dependent on the method of connection but that's technology for you.
All is well, and your wifes surfing and downloading speed shouldn't be affected, remember, most internet connections don't go above 8mbps, so 54mbps is plenty fast.