I have no answers for vBulletin (I don't use it), but you could just do a backup via phpMyAdmin >.< That is if nobody comes up with the solution you're after.. It's just as easy too Chuckun
http://www.forumansion.com/showthread.php?tid=10010 I wrote a guide with images on how to do it. It works with whatever forum software and stuff.
If you are running vB4, the backup function is not there anymore. You can install MySQLDumper, it's easy, powerful and free
Just use mysqldump in shell. Sometimes the dump is just too big for PHP to handle so it doesn't matter if you use vbulletin or phpMyAdmin. It will not work. Here's a link; tizag.com/mysqlTutorial/mysqlbackup.php Hope this can help you!
no use mysqldumper, I have been telling people to use that since I first heard of it. Do not use phpmyadmin, I tried to restore a database that way and it failed. Thankfully I found mysqldumper before switching hosts. Many errors that you encounter via phpmyadmin like "wrong sytnax" blah blah blah... can all be avoided with mysqldumper, same backup was used on both mysqldumper & phpmyadmin. Phpmyadmin failed where mysqldumper did not, after that, it became the software of my choice.
Phpmyadmin is perfect if you know what you're doing. As long as you export it correctly, and import it correctly then you'll have no problems. If you're not confident with it though, then I guess people're finding mysqldumper easier, so go for that
Chuckun, you get problems when you have big databases, say 700 MB. phpMyAdmin simply can't handle that (because of limitations in PHP). I just use command line with mysqldump, however mysqldumper looks good from the quick overview.