Let's say you have an application that only runs well on Windows XP, doesn't have a Linux equivalent, and doesn't run worth a darn with CrossOver Linux on Linux Mint. Is there anything you can do to have your XP cake and your more Linux icing too? Yes, yes there is: Use a hypervisor to run Windows XP in a virtual machine (VM).
A VM enables you to run a guest operating system on top of another operating system. From the guest's viewpoint, it appears to be running on its very own PC, but it's actually running within a limited virtual sub-system of your PC, a VM. The VM, in turn, is managed by a program called a hypervisor. There are many excellent desktop hypervisors for Linux such as VMware Player, Linux's built in Kernel Virtual Machine (KVM), and my own favorite, Oracle's free VirtualBox. I prefer VirtualBox because it's the easiest to set up and run VMs on.
Neither VirtualBox, nor any other hypervisor, makes XP any safer to use. As security holes start to appear in XP in its retirement, those holes will also appear in XP running on a VM. What VirtualBox can do for you is enables you to run XP only when you need to for specific applications and with restrictions, such as turning off networking, that will make it marginally more secure.
VirtualBox, like any hypervisor, likes all the system resources it can get. Therefore, if you want to migrate your old XP box to Linux Mint and you have an older PC, you may not be able to use VirtualBox to run XP. In my experience, you could squeeze XP on top of Linux Mint and VirtualBox on a system with 1GB of RAM, but it's going to be ugly. You want at least 2GBs of RAM and a 1GHz AMD or Intel processor.
I go into detailed instructions on how to set up VirtualBox in the gallery so I won't bother with that here. What I can tell you is that when you run XP on VirtualBox you get the complete XP experience. For all practical purposes you're running real XP. It just happens to be running on top of Linux instead of the native hardware.
You can also set VirtualBox up so that both your Mint Linux system and your XP guest operating systems can share files using the same directories or even copy and paste to applications from one operating system to the other. Once you get comfortable with running two operating systems at once, this can be very handy.
What all this means is that with VirtualBox you run all your XP applications on your Linux system with little fuss or muss. Just be wary of any XP programs that require network access, since that's the way the hackers will be trying to get to your virtual XP system just as if were running normally on a PC.
Is it worth doing? I think so. By keeping XP on a VM, instead of running constantly on a PC, you'll be more conscious of running it rather than falling into the dangerous habit of running XP like there will still be patches coming. By running XP in a VM only when you must for special applications, you can start breaking yourself of the dangerous XP habit. Over time, you'll find yourself running more and more of your day-to-day work on Linux, and eventually you can give up Windows once and for all.