Why not use videodownloader 1.1.1? It is a plug-in for firefox that enables you to download from a number of video streaming websites like youtube, metacafe, iFilm, Daily motion etc etc... (They claim that it supports around 60 such websites).
Also, you can use it with netscape 9.02b (that is what I am doing) and yes simultaneous download is possible.
If you don't wish to download any software but still want to download videos simultaneously or one at a time then use: KeepVid
Use Ultraget dude, it has the shutdown option and can also login to you youtube account (for age conformation that is needed before viewing some videos)
I tried out Real Player 11 & it's so good at extracting videos from everywhere. It's cool. See any video on ur browser, get it. Isn't it Simple? try it out.
There is a site javimoya.com to get download links of online vids. but its so overloaded and often results in an error. hence its recommended to use seperate utilities for the purpose....