Find & download, 'Roxio easy media creator' (7.5 or later if you can)
an excellent, easy to use video editor/converter, sound editor, dvd creator, disk burner etc.
It seems to recognise just about every codec/format there is, really, really good, and other than the HD videos produced by Andy Gibbons (Mid week meet) which are High def, and were edited with Adobe Premiere pro, all the home-grown videos hosted on this site are created/edited using Roxio 7.5.
for general use on PC's and internet generaly, save as .WMV's (Windows media Video files)
"I Agree with everything you say really!" - John Cooke to Jon Fuller - 26-01-2013