I had to work on deploying SQL 2005 service pack 2. I tend to look at the version numbers so I can make sure the upgrade is consistent. Well, SQL 2005 was a bit interesting.
http://support.microsoft.com/kb/936305/en-us
http://blogs.msdn.com/psssql/archive/2007/04/06/post-sql-server-2005-service-pack-2-sp2-fixes-explained.aspx
If you have to deploy SQL 2005, you might want to read up on the posting from the PSS team.
I'm working on some perfmon issues related to sql server. Here are a few links with articles covering which perfmon counters and values should be used. If you are in a position where you have to troubleshoot these types of things, this is a must read. A fellow co-worker passed along the first two, which are really good.