You might as well use a regular sim, because adding animations to a deco object is much harder than making a pose/animation box or a few extra "background" sims. You'll also have pretty much the same polycount and textures.

For storytelling I tend to make a few families with various sims, dress each sim up in different clothes and hairstyles, and use those as "extras". Make them look a little generic in face structure, and you're good to go. You can change pretty much everything except skin and eyes easily ingame, and for eyes you can use contacts (makeup or accessories).

You can use a summoning mod to add the sims to the lot temporarily, though I do advice to not save after doing so. Keeps things a bit neater.

Only having NL and Uni would reduce the usability of mods like the Insimenator, since it's based on hidden or less available ingame functions, and doesn't actually add something new. Functions that come with EPs you don't have will not show or in some cases won't work properly.

Not sure which EPs are needed for the Family Tree to work, but I'm guessing one of the EPs you don't have added some of the functions, and that's why it's not working.

Could be you need the Pets pack (or above?) for these mods to work. Insim is supposed to be backwards compatible, but I'm pretty sure the SimBlender needs Pets (or above?) to work.

Sometimes you'll also get the option to ask another sim to move in if they've got a good enough relationship - but it's been so long since I played anything near vanilla style that I can't remember if that only works for lovers/fiancees.

Which EPs/SPs/game version do you have? Makes it easier to figure out which mods you can use.

The Insimenator mod has a Family Tree object (looks like the ingame Bonzai tree). One of the options is to add sims to the family permanently.

Are you sure you've put the mod in the right folder and all? Make sure to unpack it from the archive, and put it in your Downloads folder. I've used the latest version since I installed M&G back in 2009, and it works fine (for me and most other people who still use it).

I use the SIM version (adds menus to sims, spawn menu for the Insim objects, and menus when you click on the ground). The OBJ version only adds the objects so you have to find them in the buy menu (Electronics/misc, I think). Not sure about the DEST version.

Rar and zip files don't show up ingame. You need to unpack them, as the game can only read package files.

Which version did you download? SIM, OBJ or DEST?
Also, remember to make sure CC is enabled, and that you've put the ".package" file in your Downloads folder, not the zip/Rar file.

The current version should work for all game configurations (up to and including AL/M&G/UC)

You can use an USB stick, an external harddrive or any sort of transfer method with enough space to do a backup of the folder.

If you're unsure how big the folder is, right-click the folder and choose "properties". You'll see the size there. It can be nice to know how much available space you need.

I can't see any items that looks immediately suspicious.

I think I misunderstood your first post (just a FYI, but it's much easier to understand you if you use proper grammar and punctuation in your sentences). If you have all the EPs you need the AL/M&G version of Inteen, and any other mods you want to install.  

When installing the game, go ingame and make sure everything is working fin before you start adding CC. That way you know it's not the game itself causing issues if you experience problems.

Also, doorbell sound? You mean some kind of Windows sound?

Sorry, didn't see "Sims 3" above.

They're in Sunset Valley, 13 Skyborough Boulevard in a large Victorian manor by the Pleasant Rest Cemetery (according to the wiki: http://sims.wikia.com/wiki/Goth_family & http://sims.wikia.com/wiki/13_Skyborough_Boulevard)

Pleasantview, right? Should be the brownish "gothy" house somewhere in the middle of the map.

Not sure Inteen is compatible with just Double Deluxe. Which version did you get? With Double Deluxe it's probably one of the versions between 11 and 15.
http://www.simbology.com/mods/index.php?dir=inteen/inteenimater/&sort=date&order=desc

The Inteen B pack is commonly highlighted because it changes ingame behaviour.

It oculd most definitely be something in your downloads. Have you tried playing the game with no CC to see if the crashing issues still happen?

Most downloads should go in the "C:\Users\USERNAME\Documents\EA Games\The Sims 2\Downloads" location, which you should be able to access more easily if there's a "Documents" button somewhere in the Start menu (or whatever Win10 uses as a start menu - depending on the version, you can get a start menu like with WinXP). Some variations of the file path may occur, but you want the "Documents" or "My Documents" folder.

If you have (or get) the Ultimate Collection, the "The Sims 2" folder may have a slightly different name.

I think the Insimenator is downwards compatible to at least University, not sure if it works properly with only the basegame (some functions belonging to the various EPs will be missing if you don't have those EPs), but I'm not sure if Inteen is downwards compatible. You'll want the version that works with your highest EP (or SP, in a few cases).

If you want to install more EPs, try to do it in the correct order (order of release) - but if you can't, that's fine. You do not need to uninstall, but you may want to take a backup of your saved game (everything in the "The Sims 2" folder mentioned above) just to be on the safe side.

If you want to remove EPs it's often safest to uninstall first (not sure if it's 100% needed, but you do avoid some annoying issues that might crop up), and you should always start a new game if uninstalling single EPs, because otherwise you may get big issues with your game because of missing content. If uninstalling AL or M&G you have to start a new game, since these run on a modified game engine and may make the current neighborhoods and lots unplayable. You may also want to take a backup of your current game first, if there's anything you want to keep in case you reinstall the EPs.