which version should i use for ruby 1.8.7 in Cent os 5.5 x64

ruby 1.8.7 has p302 and p330 versions, i want to install ruby in centos x64 and rails of 2.3.5, but i am not sure which version should i use ?

Could someone give me some recommendations for me? Thank you in advance.

As a general rule, you should use the latest version unless you have very specific reasons not to.

You should also update Rails to 2.3.12 if possible to address some security issues in earlier releases.