Currently, there are many video sharing websites with lots of video content.
For example, nearly 500 cartoons are available to view online from this link,
http://www.youtube.com/profile_play_list?user=DiggUser
It would be better to download and view these videos rather watching online,since downloaded stuff can be shared with friends, but most video sites such as Google Videos, YouTube etc dont allow you to download the videos.
Here's a method to download such videos.
Downloaded file will be in FLV format (Flash Video, extension .flv)
Here's the procedure,
Step 1 : Copy the URL of the page which contains the video
Step 2: Goto www.Keepvid.com
Step 3: Give the URL in the search box of keepvid.com and hit "Download"
Step 4: Keepvid.com gives back an URL, Right click on it and select "Save Target As"
Step 5: Save the file as "filename.flv", dont forget the double quites and the .flv extension
Step 6: Open the downloaded file with FLV Player, if you dont have FLV Player, download it from here,
http://www.simtel.net/product.download.mirrors.php?id=95201