Let me begin by saying that if you are still running Windows XP, then the answer is a resounding YES! Windows XP, although having been a longtime friend, is no longer a safe and supported operating system; it is most definitely time to get away from it.
If you are using Windows 7 or newer, you are probably starting to see a Windows icon down by your Clock, in the System Tray. This is the Upgrade Reservation icon for Windows 10, which I bet just caused you to do a double-take because if Windows 10 is free, then why do I have to reserve a digital download? The actual reason is tightly sealed up in Redmond (Microsoft Headquarters) but the going theory is that Microsoft wants the upgrade to be as smooth as possible, so by doing the reservation they can judge how much resources they will need to ensure that things don’t crash as millions of people (Microsoft hopes) are all upgrading to Windows 10 at once.
So, one may ask at this point; is this too good to be true? Is Microsoft truly giving away Windows 10 for free? Well yes and no; Windows 7 Enterprise and Windows 8/8.1 Enterprise users are not eligible for the free upgrades to Windows 10. In addition, Windows RT/RT 8.1 users are also not eligible for a free upgrade. However, Software Assurance subscribers using the Enterprise operating systems will be able to participate in one of two branches: the conservative, Long-Term Servicing Branch (5 year contract), or the somewhat more aggressive Current Branch (1 year contract) for Business. For anyone using the Home and Pro versions of Windows 7 and Windows 8/8.1, the upgrade is free. This is good news for many Small-Medium Business (SMB) owners as they typically wouldn’t have the Enterprise versions with Software Assurance (SA), but rather would run the Pro version of Windows.
Here is a matrix of how the desktop/laptop/tablet upgrades will work, with them all being part of the Free Upgrade tier except the Excluded Editions:
Windows 7 Starter will be upgraded to Windows 10 Home
Windows 7 Home Basic will be upgraded to Windows 10 Home
Windows 7 Home Premium will be upgraded to Windows 10 Home
Windows 7 Professional will be upgraded to Windows 10 Pro
Windows 7 Ultimate will be upgraded to Windows 10 Pro
Windows 8.1 will be upgraded to Windows 10 Home
Windows 8.1 with Bing will be upgraded to Windows 10 Home
Windows 8.1 Pro will be upgraded to Windows 10 Pro
Windows Phone 8.1 will be upgraded to Windows 10 Mobile. The availability of the upgrade may vary by hardware maker, mobile operator or carrier.
Windows 7 Enterprise, Windows 8, Windows 8.1 Enterprise, and Windows RT/RT 8.1 are excluded from the free upgrade offer.
So, in answer to our original question, the easy answer is yes; if you are running Windows 7, Windows 8/8.1 then you should upgrade. Windows 10 has a lot of improvements, with one of the biggest and most talked about being Continuity Mode. This means if you are on a tablet you will get the Modern UI tiled interface and if you are on a Desktop you will no longer get this interface. You also have the Start Menu back as it was in Windows 7, but with some improvements. Windows 10 also has significantly lower System Requirements than previous editions, which means you may not need that hardware upgrade right away just by simply moving to the new Operating system.
Windows 10 will become Generally Available (GA) on July 29, 2015, so mark your calendars and plan for the upgrade. One of the planning steps that cannot be emphasized enough, as with any upgrade, make sure you have your data backed up!