Suse 8.0 or Greater PostFix or SendMail which is Better

Dear Friends, I have a LAN with 10+ W9x Nodes and a Linux Server with suse 8.0 I have a POP mail Account with my ISP. I would Like to establish a Internal Mailing system which will enable my 10+ different users to mail each other as well they should be able to send mail outside. Similarly they should be able to collect mail from the pop mail account of mine which are aimed to a specific user. the outsider will address mail to internal user as follows "Internal User" < myac@mydomain> and the internal user will write reply to as "Internal User" < myac@mydomain> which MTA is suitable for this task Postfix or SendMail ? Our experience with Linux is just 6 months to 1 yr. Thanks Best Regards R. S. Patil