Divx / codec...

[eRock]

If I have the latest DivX, do I also need to DL the Nimo Codec 5.) too?

[easy01]

If you plan to encode the movie in Divx you don't need anything else, except the codec

I 'll recommend you a Gordian Knot if you plan to do some serious encoding.
There are great Turorials about the Gordian Knot at http://www.doom9.net

[eRock]

No serious encoding at this time, but thatnks.