VPN Recommendations?

Hi all! I would like to set up a VPN between two SuSE Linux computers (v7.3). Can anyone recommend a good howto or software package? (Free of cost, if possible.) I looked into the VPN-Mini-Howto from linuxdocs.org, but got stuck after a while because pty-redir doesn't seem to like kernel 2.4. And anyway, it looked rather like a home-brew than a proper solution. Currently, I am going through VPN-Masquerade-HOWTO. Is that good? Any tips? Thanks! And as a side note (but less urgent): Is there an quick'n'easy'n'secure way to establish a VPN between a Windows XP computer and SuSE 7.3? Where to start reading? Best regards and thanks for your time, Michael