Is there a way to delete a single Sim from a household?

Here's my issue: I recently had a Sim join my household and now my Sims are disappearing, reappearing and refusing to do basic functions.

It seems whenever they go to sit down they vanish, then reappear elsewhere on the property.

If they're hungry, they won't eat. The bus won't arrive to take the kids to school, and no one can leave the house.

I tried playing another Sim family and the game locks up.

And it all happened when this one Sim joined my family. And upon joining my family she disappeared. I click on her icon and nothing. I even tried having my Sims move OUT of the house, but the game just keeps processing.

So, any ideas?

http://www.sims2wiki.info/wiki.php?...lp:System_Specs

* Operating System: Microsoft Windos XP Home Edition (5.1, Build 2600)
* Processor: Intel(R) Pentium(R) 4 CPU 2.6GHz (2 CPUs)
* Memory: 3070MB RAM
* Page File: 1371MB used, 5638MB available
* DirectX Version:DirectX 9.0c (4.09.0000.0904)
* Dell Model Number: Dimension 8300

==Display==

* Name: Radeon 9800 Series
* Manufacturer: ATI Technologies Inc.
* Chip Type: ATI Radeon Graphics Processor AGP (0x4E48)
* Approx. Total Memory: 128.0 MB

* Main Driver: ati2dvag.dll
* Version: 6.14.0010.6706 (English)

==Sound==

* Name: SoundMAX Digital Audio

Also, I had added the Super Speedy Book mod, too.

I'm not sure if it's the mod or the Sim that's causing the problem.

Whenever a Sim tries to use an object they disappear then re-appear without having used the object.

I was able to have one Sim go to the gym and it was filled with Sims frozen in position with my Sim invisible.