I'm currently at the episode where they replace Delenn in the Gray Council with Neroon. For some reason I thought that happened much later, this means the council was in this state for two full seasons?
Nope. After a year, the council was eliminated entirely when the Religious and Worker castes split off to fight the Shadows, while the Warriors who'd been training for the most awesome test of martial prowess imaginable for thirty generations sat it out once it actually arrived.
Why did they think giving a 5-2-2 advantage to the Worker caste was a solution to this? Seems like giving any group an unbalanced majority is equally bad, so everyone's okay with this because they were the least combative caste in the last couple years?
It's a very '90s end-of-history idea, giving power to the exploited (and disinterested) lower class to move past all the old scores and petty bickering of the prior generation of leaders (remember Sheridan's "We'd be better off if politicians were men of the people" routines?) and focus on "real problems" and not the made-up issues politicos want to debate. Of course, the 21st century has done a pretty good job of wiping the "politicians are all crooks, parties don't matter, vote for personalities if you vote at all" meme out of American discourse. Babylon 5 was a very pre-9/11 story (I don't think in this era of multiple massive political demonstrations a year, including in the first world, it'd make as much sense for Ivanova to foreshadow Clark's takeover of the government based on Santiago's chin-strength).
On the other hand, it's also possible that the Worker caste is most populous numerically. Everything in Minbari society seems to be divided equally among the three castes (for instance, as alluded to above, a third of their ships are owned by each caste, even though under normal circumstances they'd be run by integrated crews), but we never heard of any kind of quota system or anything ensuring they'd be equally distributed (indeed, the quick-and-easy "Calling of my heart" system for switching castes is pretty strong evidence against it), and economically speaking, you'd need very few priests and soldiers compared to the number of miscellaneous citizens to keep society running. Plus, with the Warriors always off fighting, and many of the religious caste people we've met being cloisters like Lennier (given how he crushed on Delenn, didn't seem like there was a lot of hanky-panky going on at the Temple), it's possible the Workers are the only ones who are raising children in any number.
Could someone tell me what de-interlacing actually is? I gather it has something to do with those kind of black splotches that sometimes show up on things you watch. Often it happens when up against black clothing or nighttime scenes or just when the show or movie has some kind of dark moody lighting.
Those sound more like data-rate issues. Interlacing problems are when there are thing horizontal stripes in moving objects on screen, like you're looking at it through a comb.