Something really nasty happened to my Arch Linux just now and I don't know why...

I was switching through Xfwm4 themes when suddenly Kate crashed and brought down X with it.

I started X back up, and Xfwm got hung up, I had to switch to another VT and run "killall X". I tried replacing xfwm4 with pekwm (but still with xfce4-panel) in .xinitrc, same thing. I deleted all my Xfce config files and tried again. The mouse didn't even move. The keyboard didn't work, not even the keyboard light would come on and I couldn't switch to another VT. I was forced to use the Reset button and hope it wouldn't ruin my hard drive.

It booted up fine, I purged all xfce4-related packages just in case while still in CLI mode, and I ran "xinit /usr/bin/pekwm" and I got into a working GUI.

I closed a window and X froze again! The window's close button just stayed presses after I let go of it! I killed X from another VT.

So I installed and ran "rkhunter" form AUR (I wonder why they don't have it in the arch repos, it's so much better that chkrootkit) and it warned that I might have Adore Rootkit. What should I do?

If it helps, I recently installed a few packages from the Arch Linux AUR, including "ooc-git", "ooc-gtksourceview-git", "libpng12", and "virtualbox_bin".

Since you experience both SW and HW trouble those may be related to Something Completely Different. The first thing I'd do is (calm down and) reboot the machine using a Live CD and inspect the system and X11/Xorg logs. As for the RKH warning attaching the rkhunter.log might show us clues.

Where are those logs?

BTW, I found this: http://bbs.archlinux.org/viewtopic.php?pid=696130

chkrootkit says no warnings.

rkhunter's log usually placed in /var/log/rkhunter.log.