For now I've been going through Series 3-5. They're generally the cleanest and most consistent of the earlier episodes.

Series 3 - Lots of color noise and a greenish tint, plus inconsistent framing

Series 4 - Less noise, but most episodes have a prominent gold tint to them, and the same framing issues as Series 3.

Series 5 - Fairly clean overall, but the colors can seem washed out and slightly yellow.

Here's a comparison frame taken from an episode of Series 5. The brightness is barely changed, but it looks like the blacks might be crushed a bit. However I tried to fix up the hue by lowering the red levels and upping the blue. How's it look?

Also, I'm trying to plan out the episode order ahead of time, but can't seem to find out how much runtime I'll get from a 720p video on a Dual-Layer DVD-R. I'm guessing 1 "Playlist" of 6-10 episodes should run from 32 to 52 minutes, and knowing how many of these I can fit on a single piece of media will help.