These file are usually avi file but they may be vcd in which case you would need a player that could play vcd file. Not sure of any off the top of my head you will have to loock around unless you have a vcd compatible dvd player then you can burn the files as a vcd and watch them on your dvd player.

Normally files that have cam and telesync in them they are refering to the quality of the video. Cam means that it was recorded using a camcorder. Telesync is better the video is recorded by a camcorder but the audio is recorded seperately so that you dont hear other things.
Let me know if this helps at all and what files are you tring to dl maybe i can suggest a better place to get them in avi format.