If you have been going through Skyrim, installing/un-installing mods for a while with your current save game, chances are they are finally breaking the game down. I personally would suggest starting a new game with the major mods you are sure you want to play with. I had done the same things, and recently it had seemed that CLARALUX and Lanters were messing with Realistic Lighting. When I did what the OP said to do and enable the papyrus log, I found a crap ton of erroes. I mean a crapton, I couldn't post the log on this site or through a PM if I wanted to lol! So, I reinstalled Skyrim, and selected my most favorite mods. I tried cutting back on some, but I am a mod junkie so that didn't work out too well lol. I recommend using the Mod Organizer here on the Nexus. It allows for some really cool stuff, and really good control with what mods you install. It does require you to read a lot, and to get a good understanding of how it works. Too many people take mods for granted, and think that everything should work perfectly. WRONG. Once you install a mod, you taking a risk that said mod will cripple your game. You need to check files, read instructions, go through the comments section and see what other users are saying or are experiencing( but do not take their word for it! Many people run into issues and immediately blame a mod for their issues, when most of the time it is user error! Don't be one of those people! ) When updating mods, always go over the description page and readme for instructions and see if you need to do a clean install or if you just plug and play! Yes this is all very time consuming, but if you don't want to do it, then don't *censored* when s*** hits the fan( not refering to anyone here, but there have been issues with really amazing mod authors and retarded users who drive those authors away because of stupidity on the user part )! I also recommend the Skyrim Configurator here on the Nexus. Allows for really easy and good customization with a helpfull GUI. And while I am at it, I also recommend getting the STEP guide here on Nexus as well. Has some great instructions and how-to's. Remember that mods that run by scripts are likely to leave nasties in save game if not properly uninstalled, or they just might do that anyways cause of how the mod works.
Edit: Oh and here is a link to where the Unofficial Skyrim Patch is:
http://www.darkcreations.org/forums/
They have the 1.5 beta version up to fix the various issues that 1.6 produced, such as the vanilla npc dialouge bug which can lead to broken quests. It is a must!
Edited by Killerbuddy, 03 July 2012 - 04:39 AM.