For the people talking about XP - YES it is a great O/S for those of us with old 32x bit drivers that do not work on newer O/S... but... DO NOT use WINDOWS XP still if you use the internet or worry about exploits/hacks/virii/trojans or anything like that. As of April 2014, there is no more support for patching/updating XP, apart from the monthly 'malware search tool' they give out. So, expect it to be the main focus on hackers for a long time to come, while people still use it. I personally still use it but only on a PC I use for a single task and some local networking. I wish I knew how to make the network adaptor only see the LAN and not the internet though.. as for Windows 10 vs 7 vs 8, 8 is poop and only useful for tablet/touch screen devices. Windows 7 is the current sweet spot, with the latest version/updates. Windows 10 needs 1-2 years imo until it is SP1/2 for stability and bug fixes. Never get a 'new' O/S, shortly after release. There are ALWAYS a ton of issues and patches for them. I laughed so hard when I saw people caring enough to get Windows 8 on release day. Even Windows 7, I waited until SP1, getting as much out of XP as I could. Before that, I was Windows 2000, before that, 95.
Windows 3.11/NT = good
Windows 95 = decent for a new style
Windows 98 = bad
Windows 2000 = good
Windows ME = bad
Windows 2003 = decent
Windows XP = good
Windows Vista = bad
Windows 7 = good
Windows 8 = bad/decent for new
Windows 10 = ? MAYBE good.. or MAYBE another Vista??
Windows 11 = good or bad, who knows now..
MS-DOS/Windows 1.0/3.11 to present