There are many options, but I'd say on those specs anything will run more or less fine with some tweaks/settings.

Personally I would go with KDE Plasma, because I feel most comfortable with it. It can be pretty light on system ressources when configured properly. Disable all the visual stuff (animations, blur, anti aliasing) and some of it's background modules (baloo and some other stuff that you personally don't need).

But you should take the one you are familiar with and find out how you can tweak it to be more light. Cheers