Skyrim became unplayable ever since I installed a mod Since then it's been giving me grief... even know it's been deactivated.
http://youtu.be/SrELjYqVPjM

Does anyone here know how to fix this problem?

Deactivating a mod doesn't always remove it.

Given you have no clue where to go from here, and I'm not going to start guessing, just uninstall the game, delete the Skyrim folder located in steamapps/common/ and reinstall the game fresh.

Those script errors containing "WET", did you use NMM to install/uninstall the water mod or manual?