In reply to FesteringSore:
Win 8 vs XP is a strange choice. It depends what you're using it for: that is what programs and on what hardware.
If you don't absolutely need Windows what about shifting to Linux, which is far more secure? Every version of Windows back to early 95 has a backdoor built in for the NSA and I'd suspect that newer versions might have even more spyware capability that has yet to be discovered - one of the main problems with closed source software.
I've used Win 8 for a bit. The main advantage was that it would start faster that Win 7. It also has a better Task Manager and is more suited to touch screens esp mobile and tablet PCs. It also seemed to come preloaded with far more junk programs than previous versions which again seems to be influenced by the mobile/tablet sales model.
I agree with others that Thunderbird is a great email client.