As always, there is more than one way to skin a cat!
My preference would be to control the distribution of your images centrally. For this you can use RoboCopy which will honour bandwidth limitations enabling you to sync your images overnight or over the weekend.
Here is a post where this was recently brought up,
https://www-secure.symantec.com/connect/forums/bandwidth-usage-when-create-image-task-executed
DVD's are OK, but if you must go down that route perhaps a USB disk is an option to consider too. It can often be frustrating writing several DVDs for image store refreshes, and with the occasional write/read problems it can sometimes be downright painful!
Next thing to consider is is where to dump such images so they are available to your remote sites. Following the above advice to deploy remote PXE servers (very sensible) you'll need to create an additional share (say images)on these server so that you can image off them.
This means you'll need to map a generic drive within you PXE environment, for example if using WinPE/DOS:
N:\ maps to \\%ALTIRIS_PXE_IP%\images
And then you'll have your imaging jobs deploy from the N:\ drive
This way you have one PXE automation image which will work across all your remote sites.
Kind Regards,
Ian./