The Related Link shown below will take you to the appropraite page where you can change your account information.
this is not true you can change it by going to your chanell then going to customization and then your name will be in the basic info collum and then you can press the little pencil next to your current name.
To change an email address on an iTunes account simply log in to the account and click on the Edit Account Info button and type the new address into the appropriate box.
at the top right corner click your youtube account name then go under "my videos" the in press the video you want to change under edit info and then just change the name and click "save changes"
usually your google account's profile picture is being carried over. but you can change it, just click on you profile on youtube and change your picture. See related links for more info
No you are unable to change the absence account in you tube.
You can't change your username on YouTube, though you may create a second account with a new name.
You cant change it, if you really want to change it the only way to do it is to delete your account and to do that you have to go to manage account, delete account, give a reason, and boom you have deleted your youtube account.
Just sign in to your other account. If you are already signed in but with another account, sign out.
Yes you can transfer your YouTube account to your AdSense account.
Nowadays (2014) your gmail account is managed through your Google+ profile. This also serves as your account info for YouTube, Orkut, Picasa, Chrome.
Yes.
Have you ever watched a video on youtube in which has an ad? Well that's because they are part of the Youtube partner program. It's where if you have enough views, you can start making money when people click on your ads. The reason it's there is in case you are or wnat to become a youtube partner, you can check/edit the info.