Yeah SSID hiding is a bad idea, not only does it cause problems when trying to add clients but Windows clients also spit out the SSID name when the AP is not in even range such as when connecting to a public hotspot. As FordPrefect mentioned, adding a WPA security is the best thing to do, the next is to change the default SSID and all default passwords. This will help conceal your devices identity, having an SSID such as 'belkin54g" is esentially advertising you have no idea about security and are likely to be using the default settings.