The file sample.avi is normally an included small file from a bitorrent movie rip so that you can get a prewiew of the quality of a movie before you download it. It's pretty useless really.
Rar files support splitting, which is why you have stuff like file.r00, file.r01, etc. In windows, you simply open any of the .r00-etc files in winrar, and winrar removes the contents from all the .r00-etc files at once. I have no idea how to do this in linux as I don't have any multiple .r00-etc files on hand, but try the following.
Firstly, try opening it graphically. If you are using fedora that'll be through the archive manager (system tools->archive manager). Secondly, if you want to use the command line, try using unrar on any of hte .r00 files - probably best to do it on file.r00 - and see what happens. This of course assumes that you have rar and unrar installed. If not, then go to the Rar Homepage
and downlod rar for linux. extract it with tar -xvzf rarpackagename
and then go into the newly created directory and type ./unrar -e path-to-file.r00
. The -e option is to extract to the current directory, so thats where your files will go.
Hope that helps.