New answers tagged versions
For this hardware I would recommend 32-bit version of Ubuntu 14.04.2 LTS. LTS are always preferred, especially for new users. And they are supported for 5 years. 32-bit, because there is only 2GB of RAM and 32-bit version uses less RAM. 64-bit should be almost as good.
If you're looking for an OS that has low spec requirements, then you're looking at one of three of the Ubuntu derivatives. Take a look at this Ubuntu wiki page for more info Lubuntu (LXDE) Xubuntu (XFCE) Ubuntu MATE (MATE) All three of these would be a good choice for your laptop's specifications. I would personally choose one of those three over stock ...
You can install the latest version of Ubuntu (15.04), but i would recommend you to install the 14.04 LTS version.See this http://www.ubuntu.com/download/desktop/install-ubuntu-desktop
There is no way to install Java to Chrome at the moment. NPAPI plugins are not supported on linux any more. But I have not heard of any existing PPAPI Java plugins now. I use Firefox for Java.
Top 50 recent answers are included