I tried changing my c:\windows\system32\drivers\etc\hosts file (wanted to add a new host) and... apparently, if I do, AVG will report, when doing a full system scan, that it's been changed, and will revert it.

I don't want that file reverted. I changed it and I *want* it changed.

What can I do to remedy this behavior? A Google search suggested that it be write protected, and although that is certainly something I can do, I'm not sure if that'd stop AVG from reverting it, anyway (ie. write enable it, change it, and then write protect it all over again).

maybe disable AVG (antispyware module?) from scanning the host file until after you made the change

Cudni

Try adding it to exceptions?

• Open AVG Control Centre by double clicking on its icon near the clock.
  
• Click on Tools > Advanced Settings....
  
• On the left, click on PUP Exceptions.
  
• Click on Add Exception on the left.
  
• Browse to the HOSTS file and click the Add button.
  
• Click OK to apply the settings.