Add videos to my blog

Hello, I think this is a relatively simple project but I just can't get my head around it! I have 4 videos made on a kodak play sport which I would like to embed into my wp blog. I can't do it from youtube as they are too long (20ish minutes) and in a nutshell I am just getting frustrated with the whole thing as it should be so easy but can't seem to make it work! If I save them to my laptop then upload to wp it says the files are too big. I would love it if someone could just convert the files for me and get them on my blog before I scream!! Realistically I ma looking for someone to do this at the bottom of my price range as it should be a simple and quick job! Thank-you, Kate.