A: I have found some of the best websites to watch (not download) television shows are: Hulu and Fancast. Just a side note, if you are downloading a television show, that is illegal. 

A: Personally I am a huge fan of Netflix. With any Netflix account you can stream hundreds of full length (advertisement free) movies. Hulu also does offer a limited amount of movies. If you are downloading free full length movies, that is illegal.  

A: As far as it being legal, yes the program is legal but only if you are using it to download files that are not copyright protected. Let me rephrase that for emphasis, it is illegal to use file sharing programs to download copyrighted music, video, images, software, or files. 

As far as the program being harmful to your computer, well if you download a file that is from a virus or spyware infected computer that virus or spyware can be transferred to your computer. So yes the program can harm your computer.