Issues with FaceTime calls

Hey everyone, I’m running into this massive headache with my video calls... basically what the title says.
So, here's the deal—whenever I try to hop online and actually start a FaceTime call, it keeps nagging me to download some plugin. I follow the prompts, hit "get plugin," then "download plugin," and everything seems fine until the final step. When I click "install plugin," it just spits back an error saying the installation failed because the web extension needs Windows 7 or anything newer... but I'm still stuck running Windows XP.
Then, when I try to just download the actual app, it installs totally fine, but once I open it up, I get hit with another wall. It tells me there was a problem logging in because my version of Internet Explorer is "outdated" and that I need to update it before I can even try again.
Does anyone have any clue what the move is here? I mean, should I be looking for some older versions that might actually work, or am I just totally stuck unless I bite the bullet and upgrade to Windows 7? Is there some other workaround I haven't thought of yet?

Here you go—these are some older versions that actually work with Windows XP.

http://skype.en.downloadastro.com/old_versions/

But honestly? If your computer is even remotely powerful enough to handle Windows 7, I’d say just ditch Windows XP and upgrade. Microsoft stopped supporting XP ages ago, and let me tell you, it's becoming a massive security headache. More and more apps just won't run on it anymore, and you're basically just asking for trouble at that point.