The only safe & LEGAL sites to get PC games are the major digital distribution platforms.
* Steam (by Valve) --
http://www.steampowered.com
* Origin (by EA) --
http://www.origin.com
* uPlay (by Ubisoft) --
http://www.uplay.com
* Good Old Games / Galaxy (by CD Projekt) --
http://www.gog.com
All these platforms are safe & legal, since you have the purchase the games to download them.
3rd Party resellers like Humble Bundle (
http://www.humblebundle.com ) Utilizes these platforms (in additon of have DRM-free options) & is highly respectable as well.
If you're not willing to pay for the games, you're on your own since you're breaking the law & you head into questionable territory since those downloads can include unwanted extras (viruses, malware, ect.)