Why am being cut off on you tube while watching dvds and when I retry to open I fail to get back on
There may be a number of reasons for this behaviour.
1. some Internet Service Providers, those who provide 'uncapped' internet, tend to limit the amount of streaming media its customers may make use of at any given timeframe.
2. Youtube generates links to videos 'on-the-fly', meaning you can't copy the link to a video today and watch that same video tomorrow.. as the link would expire. You mentioned that you were watching DVDs, which means that it was not a short video, and the chance of the video link expiring due to elapsed time is a possibility.
3. Do you get an error message on the youtube page when you get cut off? If so, it might be due to either a fault on their server(s), or a fault/noise on your ADSL line, which caused the download to your cache/memory for viewing to stop.. clear the cache before attempting to open the video again:
Here's how to clear the cache in various browsers.
Chrome: Go to the wrench menu, go to "History" and click on "Clear Browsing Data." That's about all you need to do.
Internet Explorer: Open up Internet Options, and navigate to the "General" tab. Once there, click on "Delete Browsing History."
Opera: On the menu, select Tools->Delete Private Data. Once you've done this, check all the options, then confirm the deletion.
Firefox: Open up the options menu, and locate the "advanced" pane. From there, go down to "Network" and look for "cached web content." There'll be a button next to the information on how much space that says "Clear Now." Click on it.