Importing a feature from higher version(2.74) to a lower version(2.65) Currently I use blender version 2.65(portable) as the recent versions will not run on system due to lack of necessary "hardware accelerators". But there is a particular option in the recent versions which allows me to see the 3D window in a rendered view. Is there any way I can import this facility of the recent versions to use it in the older 2.65 version? I have both the zipped folders(2.65 and 2.77 windows 32) with me.
No. 

Features are not separate files or anything similar that can just be copied over. 

These kind of features are added by modifying parts of the blender code and then recompiling it, and generally depend on a number of other changes and are quite interlinked with the rest of the code, so that even if you were familiar with blender development, backporting to an old version of the codebase would be extremely hard.