How do I join two .rar folders?

[Steven Vollom]

Dear Matt,

I downloaded a movie called 7 Pounds.  It is a .rar.  It has the problem that 
wasn't apparent when you were helping me join .avi's that were downloaded 
as .rar's.

After being unsuccessful using unrar, I attempted to play the movie using Ark 
to uncompress the .rar.  When the title bar shows this as a reference to what 
I am 
doing, "file:///media/sda5/CompletedDownloads/7.Pounds~DvdScr~Ac3~maz/Cd1/7P~maz1.part01.rar -  
Ark", the name of the file in .avi form is, "7P~maz1.avi".  Double clicking 
on that title opens the movie, but I cannot cut and paste that file into a 
folder for future avimerge.  It opens the movie, but takes forever to open.    
When I attempt to do the same task using the konsole, I keep getting the rar 
as not a Directory.  Will you step in and straighten me out again using the 
konsole to do the work?  Thanks if you are willing.

Steven