Yes it does answer the question.

Process making the changes generates the log records and puts them into the log buffer (logs the changes). Log writer writes the log records to...

Google: log buffer. 🙂

It's...

Table definitions, index definitions and execution plan, as per http://www.sqlservercentral.com/articles/SQLServerCentral/66909/

Would need to look at the exec plan to say anything useful. Could be a bad execution plan for one reason or another and the query is just running and...

Close enough.

Lazy writer does not do writes to the transaction log.

and the undo record is logged in...

Please read through this - Managing Transaction Logs[/url]

Once you get log backups running again you can do a once-off shrink of the log to get it back to a reasonable...

Fully expected.

If it's bothering you, you could do some analysis of what indexes are getting rebuilt the most and reduce their fill factors so that they fragment less and hence...

Please read through this: http://www.sqlservercentral.com/articles/Transaction+Log/72488/

http://www.sqlservercentral.com/articles/Indexing/68439/

http://www.sqlservercentral.com/articles/Indexing/68563/

http://www.sqlservercentral.com/articles/Indexing/68636/

http://sqlinthewild.co.za/index.php/category/sql-server/indexes/

Seek - navigation down the b-tree of an index to locate a row or the start or end of a range of rows.

Lookup - single-row seek on the clustered index...

Please read through this - Managing Transaction Logs[/url]

Yup, the indexing in sharepoint is terrible and if you add any useful indexes it will probably perform better. If you then call MS support with any problem, they'll pretty...

You can create anything you like in master, you probably shouldn't in most cases, but you can.

You can't add indexes to a sharepoint content database without losing all support.

Is it IO-bottlenecked?

Are those 5 files going to be on separate IO channels?