A little more info:
1]

  • Standard Avast checks for updates as soon as you connect to the internet.
  • After that (if you stay connected) it checks for updates every 4 hours (this can be changed in avast4.ini)

2]

  • e-mails are automaticly protected if you have a NT based OS and don’t have any specific changes made to the email. (eg: to get a spamfilter to work)
  • Downloads are standard checked by the on-acces provider. (depends on your settings)
  • File sharing can be checked (for most populair p2p applications) with the p2p provider(s)

3]

  • As said in my previous post. The Pro version has a sheduler option build in.
  • For the home version you need to use the tasksheduler.
    (there has to be a difference between paid and free :wink: )

4]
hmmm, there is no 4 ;D
Well let me make 4. Read the help and do some browsing/searching on this board.
All the questions you asked are already answered multiple times here.