The glue that holds the prequels together is Palpatine's arc. From TPM to ROTS, Palpatine's rise in the Senate hierarchy and eventually as Emperor is Lucas' storytelling skills shining like never before. This is why TPM is an enjoyable ride for me, even with all of the Jar-Jar shenanigans and the sterile, cold environments of Otah Gunga and the final land battle. The prequels are uneven, no doubt, but when they hit their mark it's like watching myth and fantasy and history all colliding with finesse. Palpatine's portrayal in ROTS was a real treat to witness. The Emperor of ROTJ was back (technically born, but you know what I mean), with all of the wicked and slimy personality that makes a truly great villain absorbing and hypnotic. Ian McDiarmid's acting in the prequels is the best of anyone in the entire series, bar none, and much of the prequels' success and focus all points to his instrumental contributions. It's no coincidence that much of the dialogue McDiarmid was given is the strongest material Lucas had written during the course of these films, too. The politics may have bogged down the pacing of the films and bored more than a fair share of people, but if you ask me, it's what made the prequels worth the effort in the first place.
I will always have a place for SW in my heart, and will always respect George Lucas (he's given me much joy over the years, and both his SW and Indy sagas are two of the greatest stories ever told in film, IMHO), but in the end, the prequels are just good entertainment, rich in visual invention, mismatched storytelling, and a mythic core vying for the heavenly stars, even when they don't always reach their ambitious grasp. George Lucas' good intentions ring true even when his dialogue doesn't or when the pedestrian seams of his directing show through. So, yeah, I like the prequels, even love them in some spots, and think there's more worthwhile in the trilogy than not.
Nigel St. Buggering, it's interesting that I agree with you on the weakest of the SW lot (RETURN OF THE JEDI), but find THE TWO TOWERS to be the strongest of the LOTR trilogy. Aragorn's arc is TTT is my favorite of the entire series, which is why RETURN OF THE KING felt like a letdown of sorts.
I liked ROTK, but it had some glaring problems that I could not simply look past with ease. For one, the relationship between Aragorn and Arwen seemed a random, second thought in ROTK, which REALLY shocked me considering their love story was integral and developed in both FOTR and TTT. And then you have Eowyn's nonchalant reaction to Aragorn's rejection, something the Eowyn of TTT wouldn't have accepted. It didn't even seem like she cared for Aragorn anymore...out of the blue.