I have recently left the M$ fold and am finding myself quite lost in this world of GPL's, Open Source and Linux. I'm managing to get buy for the most part, but one problem seems to escape my grasp.

I'm sure many of you are just like me, and dread the thought of reading through a couple 300-page manuals just to find out it can't be done that way. So I turn to you instead, in hopes someone out there has the patience to explain a solution to my problem. Please let my lazyness win, I am studying Linux now ... just a long ways from learning how to do this:

We have two computers, connected to the internet via PPPOE and a Linksys EatherFast Cable/DSL Router (BEFSR41 v.2). One is running Mandrake 10, but my wife isn't ready to give up her WinXP.

A friend pays me for doing some babysitting with 2 old computer systems. The better (newer) of the two is a generic mini-tower with a (150MHz?) IBM (Syrix) 6x86. I've installed a second network card, and removed the modem, sound and COM card. Debian (9?) is the only distribution of Linux that I've been able to get to run on it, but it doesn't have issues with any of the hardware and can access the internet through either network card (tried pluging the router into each, both worked fine).

The 6x86 processor evidently has some issues with Linux, and I have been unable to sucessfully re-compile the kernal.

Okay, it's been a bit long-winded, but I'm finally getting to the point. I would like to set up this 6x86 between my PPPOE modem and my router, enabling it as a fire-wall or whatever to keep our comptuers "safe". I would also like to set up some kind of SMTP server. My web host gives me unlimited POP accounts, but no SMTP. Whenever I try Sendmail or similar, services like Yahoo dump the messages in the Junk Mail folder. Don't worry, I have no intention of being a spam-lord ... I just want to be able to send Emails to customers from sales@yendoria.com.

Can this be done? Or is it one of those so-simple things that the best answer is to RTFM? Any tips, advice, instructions or suggestions would be greately appreciated ... even if it's as simple as, "Have you tried the man pages?"