In order to follow this guide, you need an installed Linux distribution (I use Ubuntu), a legitimate copy of Windows XP, familiarity with the XP installation, and Sun's VirtualBox virtualization software (free).
This guide begins with the assumption that you've already installed Linux on your system. If you need help with the installation process, go here for a refresher. I do not assume that you have any Linux knowledge, but you should be comfortable with PCs in general.
Test System Specs:
64-bit Ubuntu 9.04 “Jaunty Jackalope”
2.0 GHz AMD Athlon 64 X2
Biostar NF61S-M2 TE
Nvidia GeForce 6100; integrated graphics, 128MB shared
250GB SATA 3 Gb/s, 7,200 RPM
The first step to getting your very own XP Mode in Linux is to install virtual machine software. Since the point of this article is saving money, we're going with Sun Microsystem's free VirtualBox as our virtualization software. Click here and choose the appropriate .deb or .rpm file for your Linux distribution. I am using the 64-bit version of Ubuntu 9.04, so I'll need to click the AMD64 link next to Ubuntu 9.04 (“Jaunty Jackeloupe”). You can choose to either run or save the file.
Though it is free, this app is not open-source. This is the version of VirtualBox that contains proprietary code. If you only want open-source software on your system, you can use VirtualBox OSE (Open-Source Edition) instead. You can get VirtualBox OSE from Add/Remove in the Applications menu. Click here if you need a refresher on installing software in Ubuntu via a package manager. You can follow this guide to setup the OSE version, for the most part. Some of the steps will deviate slightly. Also, the screenshots may not represent exactly what is on your screen.
If you chose to save the file, double-click it when downloading completes. Click Install Package, then enter your password when prompted. When the Debconf window opens, just click Forward to continue installation. After the application finishes installing, click Close, and then exit the installer by closing the window. If you wish, you can now delete the .deb or .rpm by right-clicking on it and selecting Move to Trash.
Remember the Debconfig window? Now we have to add you to the list of authorized users in the “vboxusers” group so that any USB devices will work in the Windows XP VM. It's not just your Windows apps that you'll be able to use in the VM; devices too! Now, go to System/Administration/UsersandGroups.
In the user list highlight your user name by clicking on it, then click Unlock. In the screenshot, my user name is Adam Overa.
When prompted, enter your password and then click Authenticate. Now click Manage Groups. Scroll down until you see the group vboxusers, click it, then click Properties.
You should see the user list with check-boxes next to the user name of each user on your system. Check the box next to your user name and click OK. Now click Close, and then Close again. Now we need to log out, or restart for these changes to take effect. Click on your user name on the far right of the upper panel. Select Log Out to go to the Ubuntu login screen, or Restart to reboot.