Attempts to connect to wireless internet failed

A friend of mine bought herself a new computer with Windows Vista. She decided to try out the possibilities to find open wireless networks were I live and tried it through the controlpanel and "wireless networks". She found a network and got connected to the internet. I decided to try the same with my Windows XP computer which is about three years old, but didn´t succeed. The question is why? Did she get connected just because her computer is a new one with better WLAN card or is it thanks to windows vista?

When I open the connection to wireless network I find nothing, she finds one open network and three closed ones.