below is note i wrote myself last week as have no computing power that will actually handle HD and had suffered a few times trying to sort stuff so could let other people have copies
WMV is windows movie maker and is free download from microsoft, not fancy but probably a good starting place can edit clips, do transitions, credits, add photos, music, change volumes and then burn to DVD for rels
the conversion software mentioned below is free as well and compared to other stuff tried is very good
i use a biggish external drive and save the original HD stuff and converted stuff to that – bit slower but unless you have stacks of disk space you soon get stuffed
…To convert a video from HD so will play on a pc or laptop that doesn’t have powerful ram and/or a fast video card
Use Freemake video converter to convert to WMV file (must pull down options and check save quality – reduce to “DVD Quality”) open file manager and rename to avoid accidentally selecting the mpeg or MP4 version
Start up WMV editor to make into a movie – take care when importing to check/uncheck “import clips box) if checked will split into a (random?) number of clips rather than import as one file for edit
Use Freemake to upload to YouTube – will need to login afterwards to correct title/tags but means that file is automatically correctly sized to upload – can select multiple file to upload