Passwords and video

on startup, passwords are demanded for about 6 functions; how do I remove ALL passwords from my MBA?
Video auto-starts; how can I override this annoyance?
TIA

Which 6 functions?

Video auto starts where? Browser? Site? Program?

Please see screenshots on 'keychains, disc utility and hardware test '

A few places require your password to authenticate actions that might potentially harm your computer. You cannot remove those passwords and you shouldn't try to. If you do, then you lose all the protection you get from OS X..

Thanks Ashwin- BUT, why does this happen? Never in 5 years of Mac use have I encountered this...
I don't think this SHOULD happen, even if it is necessary for background operation. Think I'll ask Apple direct.

From all I know, whenever you do anything within Disk Utility (like a disk repair or formatting of a partition) it asks you for your password. A lot of apps that install any Kernel extensions or modify system-level files also require your password.