For your first question, you don't have to "...drag and drop the folder into the bsplayer.." but you have to drag and drop the movie files. And you need the proper codecs to view the movies (Read BSPeter's
Help2Help post, which link is in my signature).
For the second one (I hope you were not tring to load a rar file with BSplayer :P ), you need a program such as
WinRAR or
7-Zip or similar to un-rar that kind of files (RAR files are compressed archives like ZIP files are, and you need a compressor program to unpack them).
