I recently bought a cheap&small office laptop with intention of taking it with me and completing assignments in public places. Problem is, it chokes up and dies when running more than eight tabs on firefox. I also tried k-meleon, it has great performance but the UI is ancient and many websites that I need dont support it.
Use either Windows 10 AME (if there is SSD, extremely lightweight) or use something like Kubuntu with disabled animations and eye candy, or Lubuntu.