A couple of quick things. First off I've not used MySQL Admin so I can't offer assistance there. When you installed your LAMP, did you allow the server name to be the default "localhost"? The reason I ask this is because MySQL Admin might be trying to connect to the localhost server and if you named it something else, may be the (pardon the pun) "root" of you problem.
I've always used phpMyAdmin (it's in the repositories) for a front end to MySQL (use it at home and work). Gives a nice web-based GUI to MySQL.
It's after the fact, but there is a really easy way to install LAMP other than the manual method via CLI. I've detailed it on my website if you're interested.
Linux'd since 2005 Linux ID 422356 Ubuntu ID 15015