Disable wireless in XPS 8700

Hi:    I have 3 questions about my new PC's wireless.

Question 1:
I just started up a new XPS 8700 with Win 7 for the first time.  Right off the bat it identified about 6 networks in my neighborhood before I could even finish setting up Windows properly.  Was I exposed during that time?  I didn't have a router set up or anything.

Question 2:
I don't plan to use wireless, so I disabled the adapter in Network Connections, and confirmed it was disabled in Device Manager, and the tray icon showed a red X.  A couple of times, however, I have discovered it to be re-enabled.  What is causing that?    Because of that, I went into Windows Services and disabled WLAN AutoConfig service.    I didn't see a way to disable WLAN in the BIOS (only a setting for LAN).

Question 3:
When I look in Network Connections, I see one for the Dell Wireless Adapter, and I also see one for "Microsoft Virtual WiFI Miniport Adapter".   I don't know why that virtual adapter is there, but I disabled it, too.  Is there a security risk for it to be enabled?

Thanks for any info.