MacBook Pro no longer recognizes USB external hard drives or built-in iSight

Question

I have an older MacBook Pro 17" Intel that I use with various external USB hard drives (8 of them). It is connected to my LG 720p 32" flatscreen and works perfectly. Recently, when visiting, I disconnected my external HDs and connected my MBP to my brother's LG 1080p and it was OK.
When I returned home and reconnected my external HDs and TV, it would not recognize the HDs and couldn't find my built-in iSight. Viewing System Information, the USB buses showed an assortment of items, such as the Apple Internal Keyboard/Trackpad, IR Receiver, and Bluetooth USB Host Controller in the buses. The High-Speed Bus showed an external HD as a Vendor-Specific Device, but none of these appeared on the desktop. I plugged in my external iSight to Firewire and it showed up in Photobooth, iChat, and Skype.
What is the problem and can I fix it myself or must I take it to be serviced?
Has anyone encountered the same problem? Got any answers?
I really would appreciate all the help I can get. Thanks.

Answer 1

I have never heard of this before, but the fact that your external iSight works shows that at least some parts of your Macv's AV circuitry are undamaged. 
Depending on exactly how you "disconnected" your "external HDs and connected" your "MBP to" your "brother's LG 1080p", I suppose it is possible that your software settings have been compromised somehow.   Here is what I would try if my system showed the symptoms you describe.
(0) Start by making a current backup if you do not already have one.
Then try any of the following you have not already considered or used.  Use them in any order you think appropriate and test after each one to determine if the problem is resolved:
(1) Shut down (do not merely restart) your MBP.  Wait a couple of minutes before starting.
(2) Test in a different user (NOT the "Guest") account: http://docs.info.apple.com/article.html?path=Mac/10.7/en/mtusr001.html
(3) Reset SMC http://support.apple.com/kb/HT3964
(4) Reset PRAM: http://docs.info.apple.com/article.html?path=Mac/10.7/en/mh26871.html
(5) Repair your startup disk: http://docs.info.apple.com/article.html?path=Mac/10.7/en/mchlp1718.html
(6) Reinstall Lion and apply the 10.7.2 Combo Update:  http://support.apple.com/kb/DL1459
(7) Contact Apple or an Apple-Authorized Service Provider for service
Message was edited by: EZ Jim