I understand that I need RCP for eclipse plugin and eclipse RCP development. However, as I have some crashes, and software installation issues, I guess I have to use eclipse classic until the issues are solved.
What makes eclipse for RCP different from eclipse classic?
I checked eclipse download page, and to me it seems like that eclipse classic doesn’t have any feature whereas RCP has a lot.
Are the features only difference between the two choices?
If so, can I download the features/plugins to use all the RCP features in eclipse classic without any problems?
All the downloads on the eclipse.org page are only predefined packages of generally available Eclipse plugins. So you can always install any plugin into any existing Eclipse installation (assuming no dependency conflicts). The package selection on the download site only determines what is pre-installed (and it is hard to disable the pre-installed features).
For RCP development you need the JDT and PDE features. Both the “classic” as well as “for RCP development” packages contain those, so it is still your choice.
If you really want a minimalistic Eclipse suited to your needs, then install the “Platform Runtime Binary” from http://download.eclipse.org/eclipse/downloads/drops4/R-4.2.1-201209141800/, which is an “empty” Eclipse. Afterwards install only your chosen plugins using the update manager.