Jerky video playback

Hello,
When for example I want to watch the live spread images, it is jerky as well as the sound. Another problem, I think the previous one, when I want to watch a show on a site which retransmits the programs of the day (I do not know if I can cite the names of site!) The connection is choppy, there are cuts every 1 / 2 minutes and it is departed.
First, I watch my videos that are delayed, it passes the replay and then everything is ok.
Second, I tried, as seen on forums, pause and restart, arrange it a little, but it cuts after 5 / 6 minutes ... and it is departed.
My equipment is new, my ISP is 9, I am non unbundled, adsl connection with a nine Ethernet box (I know nothing, but I do research and testing for days ...), upstream 460, down from 133 during my last test ...
So What is the solution for it? I thought a Wifi card, it will make things ...
I also found how to put my sound card up to date ...
I'm in windows vista version family.
Thank you in advance for your answers.

Have you tried without wifi cause it might be that your speed is not enough, then it can be drivers of your video card is not updated

So, you think that the WiFi does not help! There is no way to improve that damn speed? I can not remember how I managed to put my sound card to date to do the same with the video card as you advice me!
Well I continue to look forward ... thank you

Check out that all the drivers are up to date ...

if you have the choice, you would prefer a wired connection to wireless! Nothing beats a good wired connection! Now, if your speed is too low, it does not necessarily depend on you, therefore difficult to raise! For me, I am entitled to only about 800k