AHarris's last comment was not far off the mark. If you think you may have been infected with a virus, what I do for my consulting clients in such a case is extract the drive from their system, plug it into a dock on my Linux system, and scan it with 3 different A/V scanners (there a a bunch for Linux systems that will catch Linux and Windows virus-infected files and discs). If it is a Linux system drive, then after scanning/cleaning it, I set the root password to an empty string (no password), put it back in their system with it set to boot into single user mode (no graphics), boot up, login to root, reset the root password and any affected user accounts (or all of them if necessary), and set all user accounts to require changing their password on next login.

Yes, this is a major PITA, but the alternatives are much less appealing! I have also done all this by booting into a live/recovery CD/DVD/USB drive, installing the A/V programs temporarily in the recovery systems (along with updating virus signature files), mounting and scanning the system partitions / discs as necessary, and doing the other cruft (single-user mode, no GUI, reset passwords, etc). I only do that if I can't get the system drive to my workstation/server, like when I need to do an onsite call, though then I take my laptop and docking bay with all my tools installed. Much cleaner!

Boot with a recovery CD/DVD disc. Mount the root file system. Edit the file /etc/inittab in the mounted file system and change the runlevel to 3. Then reboot from disc. That will boot you into text mode so you can login as root and fix the GUI and other cruft.

No problem. Sometimes, these sort of things just need to be exposed to the light to correct themselves... :-)

Well the lpi (lines / inch) seems correct. Word-wrap is on, so I am wondering if it may be possible that there are fill characters at the end of the lines that may be forcing a wrap? If not in the original document, then perhaps the CUPS driver is inserting them incorrectly? I'm just trying to think of what could be causing this situation. Another thing to check is the driver you are using on CentOS. Make sure it is the same one you are using on Red Hat, assuming it would be compatible. What versions of CentOS and RedHat are you running?

It's probably a configuration issue with regard to lp or cups (the underlying printer driver). Check your default CUPS settings, and those of lp - /etc/cups/lpoptions. If it is empty, look at the man page for lpoptions: man lpoptions. The man page is for the lpoptions command. The lpoptions command with no arguments will output your current settings. See how they differ between the systems.

I don't know about KVM, but VirtualBox has the capability for a virtual machine to access serial ports as well as USB devices. Myself, I am still using VirtualBox, and have been without problems for over 4 years. I run Windows virtual machines on Linux, and Linux virtual machines on Windows...