MovieMaker does not work, I want my money back Microsoft!!!!!!!

I am extremely frustrated.  I used to make and enjoy making movies using MS 2.6 for several years.  I purchased a new laptop with 8.1, and now, neither the MovieMaker 2.6 nor the newer one works.  I cannot add music to my movie.  It says the file is corrupted.  I am so frustrated.  All the occasions for which I wanted to make family movies are just passing by.  I would like Microsoft to answer why it has sold me something which does not work.  Moderator, please tell me how do I bring MP3 music into my movie?  What is the answer?  If MS does not have an answer, then tell me how I can return my laptop which has Windows 8.1 on it?  I am still  making payments on the computer and I would actually like to throw it out the window.  I bought this specifically for making movies during my retirement.  I have been reading questions on your forums, but whatever advice the moderators are giving, they don't even follow through.  For example, about codecs.  I also get codec errors.  My goodness, is there any way to fix this or not?  Please help!!!!!  I would just like to make movies in Windows 2.6 and not have to learn movie maker all over again with the new program, which by the way is not a great program.  Thank you very much for really messing up my hobby Microsoft.  If this doesn't get resolved, I will never buy a MS product again.