Perhaps something like NetSetMan Pro's AutoSwitch feature might help:
It's easy to activate a profile with one click from the tray menu. But in some cases it's necessary to always activate a certain profile at a certain location. Then even one click might feel like too much effort.
NetSetMan AutoSwitch is the solution! AutoSwitch recognizes your location analyzing WiFi networks nearby. All you have to do is connecting one or more WiFi networks with any of your NetSetMan profiles. As soon as those networks are in range AutoSwitch will automatically launch the profile activation. A notification will show up as a countdown with a predefined delay allowing you to abort the activation process if you like.
There are some limitations in XP though, so be sure to read the documentation thoroughly first.