GOTO is certainly very useful in some circumstances. For example, a common pattern in the samba and SSSD sources is this (taking advantage of the talloc() hierarchical memory allocator):

tmp_ctx = talloc_new(parent_ctx).
*allocate memory on tmp_ctx *
do stuff or fail and goto done.
*allocate more memory on tmp_ctx *
do stuff or fail and goto done.

done:
                talloc_free(tmp_ctx);
                return result;

It's really handy to be able to just jump directly to the done: tag on any error and know that any memory you allocated is cleaned up appropriately.

There's a nice article here on setting up the LAMP stack on Fedora (or its relatives, Red Hat Enterprise Linux and CentOS):

http://fedorasolved.org/server-solutions/lamp-stack

There are two primary reasons to require logins:
1) A registration system with a captcha is highly-effective at preventing spam on your blog comments or forum posts.
2) To a greater or lesser degree, it prevents people from impersonating you. Sure there are ways to trick this (create a username that's one lookalike character off, etc.) but on the whole it makes it easier to recognize who you're talking to.

My first experience with Linux was Red Hat 6.2. I installed it on some leftover hardware I had lying around after an upgrade and followed a HOWTO I found on the web to install an Action Quake 2 server. It ran for six months without a reboot until I had to take it home for the summer.