Stop, go, stop, go, is buffering, very annoying, result of crappy internet
speed or servers.
1 Immediately try playing it a second time, don't close wmplayer, just hit
play, it should play smooth (from your cache, a copy of the file on your PC
in a temp hidden folder).
2 Download a copy of the video clip, to your PC, then play it.
KeepVid is handy to download video clips.
http://keepvid.com/
3 Upgrade your internet, ask your ISP if they have DSL2 available its
24mbps download / 2mbps upload on copper pair phone line, most
countries have it now.