It really is seldom that I advertise a product or a service, but in this special case the offer is ridiculously good. GOG offers 5 games from a selection for just 10$. And there are really great gems in the list.
All games on GOG are DRM free. That is the most important part of their business model. You can redownload and reinstall them as often as you want. And you often get pretty nice extras to your game, like wallpapers, soundtracks etc.
Always learn from history, to be sure you make the same mistakes again...