Help on which version of Mac OS X to install on my POTATO PC

Hi guys

I am confused on which version of Mac OS X should I use on my fairly old PC. The main usage of this PC is gonna be downloading,light browsing and watching YouTube.

PC Specs -

Intel Pentium e5800 2gb DDR3 1333mhz ram 1.5 TB HDD GT 610 2 GB version Intel G41 chooser

I can't upgrade the ram since the maximum my mobo supports is 4Gb And can't find any 4gb ram for less than 40$ in my area.

I tried using EL Capitan but it had lag whenever there were more than 2-3 tabs open .

Now I'm confused on which version should I try , Should I try Yosemite or Mavericks. If you guys can help me out then it would be great !

EDIT- I'm sorry if I put the wrong flair for the post since I was confused on which one should I choose "question" or "hep"