Yes, this card will work at any hot spot and is a good choice since it will support 802.11 a, b and g. While traveling you will have to set up a profile for each hot spot or Wi-Fi location that you will use. You can save those profiles to make connecting easier during future trips to the same location.
In the same manner, you will set up a profile for your home network - making sure to use security precautions and encrypting your Wi-Fi network. Once you have saved your home network profile, you won't need to re-enter that information. In WinXP you can enable your computer to automatically detect available networks and then select your home Wi-Fi network.
Remember to turn off your Wi-Fi when not in use to help save battery power and to prevent unauthorized access. You may also wish to disable automatic Wi-Fi detection while traveling so that you can manually make connections and ensure you are connecting to a valid Wi-Fi network.