Computer want to go wireless after waking up

When this laptop I have wakes up after being asleep, sometimes it goes wireless using someone's network in my apartment complex.

It does this even though I don't have any kind of wireless router or anything. I have a straight hookup from the modem to the laptop using an ethernet cable.

Someone that knows computers but doesn't know about Windows 7 said to hit the F8 key that has an antenna above it to tell it not to go wireless. That might work but I have the laptop hooked up to a 24" external monitor and if I leave the lid open or open it back up while the computer is on, it won't go to the monitor. If that makes any sense.

Easiest would be to disable the wireless adapter in Device Manager. If you want to take it a step further and the adapter is in a card slot, you can remove it completely.