look simply u dint have to change formats or any thing , just get a program called youtube downloader , and then here is how the program works , copy the url of the bookmarked videos u want to download , and then click save , and u have them now on ur computer , then burn them on the dvd u want
other option , if u have realplayer , upgrade to the last version ( SP ) and then when u view the video u will able to see a button called download this video , when u place ur mouse on the video , then a file will be saved as .flv , here u need to convert the format as .avi , if u want them .avi , or u can burn them as .flv no problem but if u will play them on other computer that dont have realplayer , then better to convert them.
to convert them , just get a program called xilisoft converter ultimate , and convert from any thing to any thing u want .
then when u done ur converting just burn them as u want
hope i helped here , contact me for any thing not clear or any other question.
have a nice day
