you know what kinda silliness you're in for. One thing's for sure, the answer to who shot Mr. Burns is the least likely citizen; and it's just that kind of subversion that such a resolution needs. And what makes it so entertaining (and the superior half of a two-parter) is that it's played to full absurdity. It's probably not surprising that Lisa is one step ahead of the police in this case, and Homoer certainly doesn't dispel suspicions when the evidence points to him.
Right from the start, Pt. II is tongue-in-cheek with an opening shower scene gag from "Dallas" (another famous episode I haven't seen and even I know about it; it wasn't lost on the writers that they'd touched a cultural nerve with this). The payoff is ridiculous enough to actually work, and that goes for the whole episode.
The whodunnit plot then begins which plays out similar to a classic Alfred Hitchcock mystery case, it was very good indeed. I like the part around the Simpson table where everyone is pointing out a possible reason for each person being mad at Burns before he was shot. One funny example: Lisa: "Dad, you sorta went berserk when Burns couldn't remember your name". Homer: "BESERK IS RIIIGGHHT!!!!". Next funny jokes: (Grampa (after everyone realizing Smithers probably shot him): "Case closed, Smingers did it, I'm going to the outhouse". Lisa: " we don't have an outhouse". Homer: "My toolshed!" As Homer is hosing out his toolshed, Moe, Barney, and the boys invite Homer to help tear down Burns' sunblocker, Homer: "I'm a coming, I've had it up to here with these rickets!" (We don't see Homer's rickets again after that moment, and that was a better choice from the writers than showing Homer with rickets the whole rest of episode). Then, when the sunblocker's torn out, we get a crushed Shelbyville and Springfield cheering joke.
As well as the jokes, we progress with the investigation on who shot Burns. First Smithers is prime suspect, and he thought he did it in a drunken rage until finding out he shot Jasper's wooden leg (and Jasper not even remembering it). And I liked Smithers' joke after being arrested "I feel as low as Madonna when finding out she missed Tailhook (Tailhook was a fest where a bunch of Navy officers sexually harassed women)(if that kind of joke was made today, they probably would've used Miley Sirus's name instead of Madonna).
Later on, Homer's the prime suspect for shooting Burns after Simpson DNA is found on Burns' suite (after Chief Wiggum's bizarre backwards talking dream with Lisa and the flaming cards)(I also liked the little joke at the DNA lab where the lab tech told Wiggum that the DNA test will take 6-8 weeks until handed a case of cigarettes and then said the test will take 6-8 seconds). I enjoyed Lisa's reasoning on how the evidence of Homer shooting Burns was not as concrete as it seemed (and us seeing Homer reaching under the seat while driving when he dropped his ice cream cone, and while feeling for the ice cream, he touched something else that lead to Homer looking guilty to the police. And then Homer touched something else (something sticky) under the seat too that appeared in part of the picture of a crucial moment, with that sticky something also being connected to a saying mentioned earlier in this two-parter story).
I also liked "The fugitive" (with Harrison Ford) reference at the drive through window after arresting Homer.
Burns being shot at the end of part one when Burns leaves that town meeting alone and full of power, he sure seemed to own Springfield now. Even Snake (at the end of part one) didn't seem that bothered with trying to stop him (when Apu asks "where's that gun slinging lowlife when you need one?" Snake nonchalant: "sorry, I was in the can"). I liked Burns' bringing up Smithers' early dispute about taking candy from babies, then without Smithers around anymore, he tries it and discovers the old saying was misleading (remember episode "Rosebud" where Burns didn't have the strength to take Bobo away from Maggie).