I don't know much about linux, but maybe try those debian stable distros (mint, ubuntu, or debian itself).

When we use linux for basic things like browsing the web, opening pdf files, editting a picture (on gimp) and so on, I don't see much of a difference on the experience.

By the way, I once installed linux on a old laptop with 2GB ram, the performance got so much better, I was even able to play simple 2D games (kingdom rush) at 60 fps, this wasn't possible on the old windows 7 it had installed.