Converting Video on laptop- quick question re: hard drive

[DSPalpatine]

I've tried to find the answer to this question on the google and the mroogle, and I'm coming up with nothing (maybe I'm not using the right search terms? I don't know- I'm usually fine at searching for answers before I post).

I'm trying to convert a 2 hour video that is currently in m4v into .dv so I can re-edit it and then burn it to DVD. It's a video a friend made but he no longer has the source material, only the DVD (it was on an external drive, not backed up, that he formatted and wrote over by accident- I know, I know, and I've already lectured him about backup practices). I was going to use MPEG Streamclip. My laptop (in the sig) is a C2D MacBook- I understand it's not exactly like a 6-core Mac Pro when it comes to converting video. My plan is to use an external FireWire 400 drive to do the conversion.

Here is my question: should the video be on the external drive and write to the internal HDD, or should the video start on the internal HDD and write to the FW drive?

(sorry if my post is rambling a bit- didn't get much sleep last night)

 

[zblaxberg]

Generally I convert video on my internal drive and save it to my internal drive then later on transfer it to any external drive.

 

[bigbossbmb]

convert directly from the DVD to your edit codec... don't compress to MPEG4 in between.

 

[DSPalpatine]

Thanks for the responses. I wish I had thought to keep the DVD with me. I only have access to the .m4v file that I created with Handbrake. At this point, I'm going to have to work with it.

I suppose my question is this- is the speed bottleneck due to trying to read and convert on the same drive, or is the speed bottleneck a function of my laptop's limitations (C2D processor, DDR2 RAM, etc, etc)? Will I see a speed difference if I'm writing to, or reading from, an external FW400 HD?

Thanks.