Besides removing the old Insim as you have you should try removing ALL hacks and CC. The easiest way is to move your Downloads folder to the desktop.
Then confirm your game is working.
Create a Downloads folder in My Documents/EA Games/The Sims 2.
If you Downloads are organized with subfolders, copy subfolders back one at a time and try the game again. And continue this until your game doesn't work. The problem will be in that last folder you added.
If you Downloads wasn't organized, Run CleanInstaller and browse to the Desktop/Downloads folder to scan it. We'll add some organization :grin:
After the scan is complete, sort on Type.
NOTE: Leave any file highlighted in RED in the Downloads folder. We will address those later.
The first thing we'll do is move your Meshes. This won't have a type, and usually have Mesh somewhere in the name. You can click on the first to highlight it, then scroll down to the last in the group and shift-click to highlight them all. Then right click and select "Move to New" to create a folder called Meshes. Once you create that folder, all the mesh files highlighted will be located in that folder. After you've got all that you can find, you can try the game again. It should run without problems though because a mesh by itself isn't picked up by the game.
Then Highlight all content such as Makeup, clothing, genetics.
Right click in the highlighted area and chose "Move to New" to create a new folder under Downloads called "Bodyshop". If you need to move more to Bodyshop, it should be under Downloads now, no need to create another new folder. Do this until all of your bodyshop type CC is in that folder.
NOTE: Some hacks are listed as clothing, game objects, and careers in Clean Installer. If you see any, don't copy those into a subfolder.
Test your game.
Do the same thing for Walls, Floors, and Terrain Paint using a folder called "Build"
Test your game.
All the recolors you can put into a folder called "Recolors"
Test your game.
Now do the same for game objects into a folder called "Buy" and yes, test it again.
This should leave you with files that don't have a type, careers and some hacks that you've identified that did have a type. Scan through the list to pick up any meshes you may have missed before. As you're looking you see some filenames that may indicate what they are and you can place them correctly. Many accessories, earrings and necklaces in particular aren't typed. Click on those, and if you identify what it is with a picture you can move it to the right folder.
What you have now is basically mods/hacks. This is where you will most likely find your problem.
All of the file highlighted in red are mods/hacks to global behavior of the game. You need to decide if you want to keep those or not. If you do, check with the source/creator to see if they are compatible with Pets (my assumption is you have Pets, because this is in Pets Help

)
If it's not compatible right click and remove it or disable it.
Now move 1/2 of the files showing in Clean Installer to the Downloads folder. I like to create a folder called Test until I know if the hack works or if I want to keep it.
Test your game. If it works those files are good. Create another folder called good and move them into it.
Now move 1/2 of the remaining files in Clean Installer to Test. Same thing. If the game works those are good.
Continue this until the game doesn't work. The bad file is in there. Move them back out of the game to a folder called Bad.
Move the rest of the files from Desktop/Downloads to Test and try them. Move them to good or bad as appropriate after your test.
Then depending on how many hacks are in the bad folder you can move them one at a time, or 1/2 at a time and check out the game.
Hope this helps.