Three FreeBSD 6 questions

[SiteRollout.com]

I'm new to this list, so here's a hello, how are you to everyone on the
list!
 
I'm coming to FreeBSD from a Linux background, so whilst some things are
pretty similar, some things are pretty different.
 
Two questions to kickstart my participation on this list:
 
1.) How exactly do I know whether I am running the STABLE or CURRENT
release, as when I run uname I can only see the following relevant info:
 
FreeBSD server4.domain.info 6.0-RELEASE FreeBSD 6.0-RELEASE #0: Sat Sep 23
13:52:48 UTC 2006     root at server4.
<mailto:root at server4.e-webhost.info:/usr/src/sys/i386/compile/SERVER4>
domain.info:/usr/src/sys/i386/compile/SERVER4  i386
 
And which file do I change to use a different release, and how must I update
the system to pull in this latest release?

2.) I'm a bit confused as to updating the system. As I understand, there are
3 areas which require updates:
 
i. Ports
ii. Security updates
iii. Kernel updates
 
I know how to perform the first two, but for kernel updates I can't seen to
find a consistent unified method with talk of the "traditional" way and the
"latest" way. What is the best way to keep my FreeBSD 6.x system up2date?
 
3.) One of my new FreeBSD 6.0 servers went down recently. This was odd as
the actual server was hardly busy, but filesystem errors came up when
booting up the server. After running fsck, server would be up for about an
hour and then go down again. This kept happening and so I initially thought
it was due to overheating. However cooling was all good, so after further
investigation and googling I diagnosed the problem as being the background
fsck which for some reason was failing, causing the server to shutdown and
upon reboot requiring a manual fsck.
 
I've fixed this by disabling the background fsck and forcing the bootup fsck
in /etc/rc.conf. At least then if the server goes down again it will fix
itself with a full fsck when booting up. My question is whether this is
okay, and has anyone experienced this same problem with their system? And
why has the background fsck been failing? Where can i find further info?
 
Any help with these questions would be greatly appreciated.
 
Regards,
Suhail.
 
www.siterollout.com <http://www.siterollout.com/>