No. Disabling an AP's SSID Broadcast function just prevents it from transmitting the SSID. The AP will still respond to any client that wants to associate with it and that sends a matching SSID.

For example, WinXP's built-in "Zero Config" wireless utility automatically stores every SSID that it receives. If your AP is using the same SSID as one that the client previously stored, the client will be able to connect to your AP, even if you have SSID Broadcast disabled.

Since the SSID is always sent "in the clear", i.e. unencrypted, it's also possible for anyone using freely available "sniffing" tools to monitor traffic near an AP and grab the SSID from clients that already know it.

In spite of all this, it's still good security practice to change the default SSID for your wireless LAN and use the same techniques used for choosing a strong password to keep your WLAN secure from casual snoopers. (Use this Google search to find an online strong password generator.)