Did you mean default or 3rd party scenery? If you have FS2000 it's possible to add the default scenery to CFS2. See my walkthrough here. http://www.simviation.com/lair/fs2kincfs2.htm

For 3rd party scenery you will most likely need various 3rd party texture libraries. The most common are the Airport & VOD textures but there are others. It should tell you in the Readme with the scenery. These are available here & on most FS sites. They only need installing once to your CFS2\Texture folder. This might help with installing 3rd party scenery. http://www.simviation.com/lair/cfs2scenclinc.htm
FS2002 scenery might not be compatible with CFS2. I would stick with stuff from the CFS2 or FS2000 sections.

PS. The link to textur202.zip in the FS2000 section appears to be dead. I'll ask Pete to fix it. In the meantime try this one. http://www.simviation.com/fs2002utilities_ess1.htm

Generally speaking the M$ sims are forward compatible. By this I mean that default files from later versions of the sim would not be compatible with earlier versions. This is the same with with most software.

It's possible to edit default textures to improve them but this will be restricted by the capabilties of the graphics engine. There are also various utilities to edit the terrain & other aspects & there are many examples of improved textures & terrain mesh already available both here & on other FS sites. If I know what you wish to do maybe I can help more.