Gotcha. You have to take several easy steps to make your wireless network more secure.
- Log in to your router settings. Depending on what router you have, you will enter something like 192.168.1.1 or 192.168.1.0 into your internet browser's address. The username will be something like 'admin'. Password will be either 'admin', 'password', or something along those lines. The username/password might even be indicated on the router itself. Just Google default router settings for whatever router you have...you'll find it.
- Once you're logged in, change this default username/password to something else.
- Change the SSID name to something else. This is the network name that other devices see.
- Change the network password. This is the password you would enter when connecting to your wireless network. Note, it is not the password you entered to get into the router settings, although you certainly could make it the same, but I wouldn't recommend it.
- Change the encryption type to the highest that your router allows (again, Google this). It should be WPA or WPA2. If not, use WEP. The idea here is to encrypt how wireless signals are transmitted from the router to a device (i.e. your xBox)
- Disable SSID wireless broadcasting. What this means is that any device searching for wireless networks in the vicinity will not display your network. So, when connecting your xBox to your wireless network, you will have to manually enter the network name (SSID) and the network password.
- Some more advanced routers also give you the capability to strengthen or weaken the wireless signal, reducing the chances of someone outside trying to get into your network, but I doubt you have that.
Okay, having said all that, keep in mind that these steps do not fully secure your network. The truth is that saavy hackers can still get in and take advantage. So, if at any way possible, just try not to associate any sensitive information when going wireless. Actually, my philosophy is: If any way possible, do not do anything wirelessly because as long as signals are being transmitted from somewhere, that automatically makes you vulnerable. I do understand that this might be considered an extreme opinion by some. Anyway, if your xBox has a wired connection (I don't know..I never owned one), just use that.
Lastly, as far as your xBox live account goes...I would contact xBox and let them know that your account has been hacked and that they should reset it/give you a new one.