Please Help ! Home Mailsystem How ??

Hello Group,
I'm new at the Linux Community. So please forgive me stupid question! )

I'm installed Mandrake 9.1 at home. Now i wanna setup a Home Mailsystem.


That's the points what i wanna do ad use:
1) I wanna pick up mails ( pop3 accounts, ssl ) for different users on
different ISP's.and store them locally with a local IMAP Server !
2) Every User should be able to access the Mails via Evolution, Kmail,
Mozilla ??
3) Want be able to send Mails and get mails via the local Mailsystem!
Masquerade the Mails with the necessary ISP Mail account.
e.g If Mail arrives from (E-Mail Removed) the mail should be avaible to local
user yxz. If user user yxz reads this mail and wanna response, the mails
should be resend as (E-Mail Removed) instead of the local user yxz@localhost.

My thoughts are:
gettings Mails : ISP => local IMAP => local User Account => Evolution or
Kmail or Mozilla as Mailreader

sending Mails: User's E-Client => postfix => ISP or Internet ??

4) Spamkiller
5) high Security
6) Viruskiller


What is a good solution to setup this things ??
If you need further information, please let me know !
Any Tips, Help and Suggestion on this are very welcome !

Greetings Siggi