Hi and welcome to LQ
For your hardware, I would recommend Damn Small Linux, Puppy Linux, Slackware or Debian - they all run very well on older/slower hardware. If you can get more memory for that laptop, I would definitely recommend it.
Whichever one you use, you will have to do a bit of reading to work out what you do and don't need - for example, neither KDE nor Gnome will give you any sort of usable speeds on that laptop.
Good luck