I am seeking urgent help for this.

I have had this problem for weeks, months, seems like years. It all started with a hack. Just one little hack (I will not name it). I tried to use it but it seemed to crash The Sims 2 Seasons. I removed it and followed all the steps in the Game Help section yet I was still lacking an answer to my problem. Eventually I uninstalled The Sims 2 Seasons and carried on playing it without Seasons (at that point I had all EP's except AL and Freetime with no SP's). Later on I got Freetime, Glamour Life, Family Fun and Bon Voyage, but was fed up without Seasons so I installed it on my computer (I run The Sims 2 on this computer, my Dad's.).
It worked alone but when installing the rest of the games it crashed with Freetime as my main EP. I jumped to conclusion and uninstalled Seasons first because it was the main culprit. After several minutes I ran Freetime but it crashed. This continued throughout all of the games (as I uninstalled them in order of release).

Months after I was determined to make it work but it seems the problem has been transmit to each of my games now. Not cool!
When I reinstalled it on this computer it crashed as usual so I uninstalled them all. Now it seems all my game are scared for life with the 'You are running the wrong version of The Sims 2. Please run (sometimes a space (Nightlife and Uni) or a character such as a symbolic character or a letter) instead.

To be exact I have attached some of the messages I get.
Even when trying to run in compatibility mode it fails.

NOTES:

Even when it comes up with a message saying "Check for a solution online" it comes up either the patch. The patch doesn't do anything towards my problem.

Even with only The Sims 2 installed it crashes.

It crashed at the loading screen and right before it got to the loading screen.

On this computer it fails to even get to the loading process with the "EA GAMES: Challenge Everything"

I'd like to add a major issue. The Sims 2 and it's components decided to uninstall themselves after their folder (program folder) was moved from the C: drive to the D: drive.

I'm sorry I cannot complete the whole system specs form.

System Specs:

==System==

* Operating System: Windows 7 Enterprise 64-bit (6.1, build 7600)
* System Manufacturer: Dell Inc.
* System Model: Dell DXP051
* Processor: Intel(R) Pentium(R) D CPU 3.40GHz (2 CPUs), ~ 3.4GHz
* Memory: 2048 RAM
* Page File: 2226 MB used, 1866 available
* DirectX Version: DirectX 11

==Display==

* Name: NVIDIA GeForce 7800 GTX
* Manufacturer: NVIDIA
* Chip Type : GeForce 7800 GTX
* Approx. Total Memory: 1016MB

* Main Driver: nvd3dumx.dll,nvd3dum
* Version: 8.17.12.5896
* Driver Date: 10/07/2010


** I fixed it!** The F or symbol was the game looking for an expansion that was not installed. It had found some of my old registry keps from previous expansions and it thought it would have a look at those. Within a click I deleted the old registry keys and reinstalled all of my expansion packs. Thanks for your help!

It's not quite clear from your post:

Did you use the manual uninstall process to clear out your registry after you incorrectly attempted to move your game installation directory to another drive? Which EPs and SPs do you have installed at the current time? Have you patched each EP? Have you modified the game in any way, by editing any of the files in Program Files\EA Games\The Sims 2 (including all EPs and SPs) or Documents\EA Games\The Sims 2? Do you have anything in your Documents\EA Games\The Sims 2\Downloads folder?

When you say that the game crashes, are you talking about the fact that the game requires a different disk than the one that you are using?

Here's my suggestion:
1) Uninstall all of the Sims 2 EPs and SPs that you have installed. Uninstall the Sims 2 base game.
2) Follow this FAQ to remove any extraneous registry entries: Game_Help:Uninstall^wiki
3) Install the base game and patch it. Run the game to ensure that everything is working correctly.
4) Install your next EP and patch it. Run the game to ensure that everything is working correctly. If it is, repeat with the next EP. DO NOT modify the game in any way or install any CC at all.
5) When you start getting an error, let us know how far you got in the process and what error you're receiving.

Thanks. I knew I missed something. I'll start tomorrow.

Edit: The Sims 2 cannot uninstall. It says that I have one or more expansions installed, and that I should remove them before uninstalling The Sims 2.
I don't but I am stuck at that.