Xorg is the default X windows system in Slack 10, not XFree86............At least it was witht the ISOs I downloaded..............I did a virgin install of Slack 10 on a separate partition and Xorg was installed................
As for the 2.6 kernel, Slack still uses the 2.4 kernel by default as it being more stable and doesn't break a lot of things like the 2.6 kernel does...........However, in the
Slackware-10.0 directory in the mirror sites, look in
testing/packages/linux-2.6.7 for the kernel-2.6.7 pkgs..................be sure to read "README.initrd" and "kernel-headers.WARNING" before using.........