Of the three series of Yes Minister that are available on DVD, this is the best, primarily because of the inclusion of the Christmas Special "Party Games" in which Hacker becomes PM. This means that the set is quite good value, for the same price as the other series, although the complete lack of any extra content is a bit disappointing.
In terms of the quality of the shows, I think that series 2 & 3 are quite comparable (better that the first), both are very good although the stories do tend to follow very similar lines and this is very noticeable when you watch episodes in rapid succession.
It would be interesting to see this series make a return, based on the current political climate - how much would change and how much would be the same? Come on, BBC, how about it!