Can someone-explain why no DRM is good? Also my other question is, Does DRM free mean i have to buy the game again in the event that my hard drive ever craps out and i have no back-up?
DRM free means basically no restrictions/copy protection. Take awesomenautghs for example. If I buy a drm free copy, which I did from humble bundle, I can isntall it on my gaming desktop, my laptop, and even my linux server and play it on all 3 at the same time regardless of if I am online or not. Basically it gives you the freedom to do what you want with what you own.
You do not have to buy another copy if you losoe your install, once you buy from gog or humble bundle you can redownload at any time just like with steam.