Thanks for all the help. After a mass search I finally found a method that worked. Here's the link for anyone not quite figuring out how to do it.
http://help.lockergnome.com/general/Sims-Error-message-install--ftopict49413.html

You'll have to scroll about half way down the page and follow the instructions to the letter.

As for background tasks, I have never had issues with that ( maybe a little game lag ), but never installation issues.

The auto run image for disc 2 is not present as it is for all the rest of the discs. This seems to be the reason disc 2 would not install, it had no run menu. This manual installation treated the entire setup as a single massive virtual disc.

Again, thanks for the help, I'm not sure I'd have hunted for specifics in manual installation without it.

As of this moment, I am happily hunting down cc and adding my own creations back to my d/l folder.

I don't want to seem a pest, but I've tried all the tricks I can think of to make this work. Nothing is working as it should. The TS2 base game stops at 73% forcing me to manually install the rest...( I have no idea exactly where the remaining components belong. ) University will install once I've stumbled through an idea of where the files go, but Night Life insists the base game is not installed properly or not at all. It's been 4 months of fighting with this. I finally got desperate enough to ask for help.

Pretty please, someone tell me where the files components belong from disc 2 of the base game. I'm shooting in the dark here. I've cleaned out the registry, I've done everything I can think of. The only answer I can come up with is a corrupted install manager on disc 2, it does not install, at all. The files are present on the disc, I can extract them, but I apparently have no idea where to put them as Night Life will not recognize it.

Thanks bunches for the info on which files to look in for the missing textures.

I ended up extracting and manually installing everything from disc 2 as none of it was present in the EA game data. Apparently the install manager for disc 2 is corrupt, missing or just not working.

Upon game launch, all went smoothly, trees and textures were in place, CAS generated a sim and all face/hair/clothing were present.

In-game play test:
Don Lothario successfully cleaned his house ( with much moaning and groaning ) to the stereo. No crash when Nina wandered onto his lot and their relationship "progressed".

BodyShop was the next test and it launched flawlessly.

All in all, I'd say my issues have been cured and my sanity saved.... Now I'm gonna burn the carefully placed files to new discs in the correct install order and use the original disc 2 as a frisbee.

Again, thanks for the suggestion of looking in the compressed file on disc, it was the solution.


Update:

Uni will install with no issues, but NL claims The Sims 2 is not installed properly or not at all. I'm assuming I've placed a file in the wrong place and NL, fickle as it is, is reading it as not there. I'm stumbling in the dark as to the exact locations each component belongs in.   

I re-installed The Sims 2 base game and noticed that disc 2 installed in roughly 30 seconds. This didn't seem right to me, but I continued the installation anyway. The other discs took what seemed a more normal amount of time.

At 75% complete the "please wait" banner pops up, the icon is created and the read me, launch or quit menu comes up.

Quit and put disc 1 in allowing it to launch from disc. All goes well. I select Pleasantview, it loads smoothly until I see on every lot "trees of crisscrossed paper" with code instead of actual trees.

Launched the CAS out of morbid curiosity at this point. It loads with not texture on the walls, but more code. I try the create key, crash. ( clean game, no cc ).

I made sure the registry was clear of sims before I tried this. The EA folder was listed on the hard drive, but not in My Documents or in the registry so no keys. I found this more than a little odd too.

My questions:

How do I figure out what files are missing?

Would it be worth attempting to rip said files from the discs?

Any suggestions would be awesome.