I use Windows movie maker to edit all my videos before uploading to youtube. Windows XP on the old desk top and then whatever came after that on this 7 year old laptop. Its not a bad editing program but no doubt there are newer and improved versions out there. I have found a few movie files that will not open in the moviemaker program but quicktime and mp4 movies are no problem. 
Edit: this laptop is Windows 7 and it has moviemaker so yours should too.