HELP!!! I'm ready to just give up (crazy Sims 3 installation issues)

Alright so...I have literally spent the last seven hours trying to figure out what the hell has happened and I'm losing my mind. What's particularly frustrating is that I had the Sims 3 plus all the expansions & stuff packs up thru Late Night on my computer, working fine, but then uninstalled it a few months ago. I went to the store and bought Generations + the 2 most recent stuff packs and now I've had nothing but problems.

I can pretty much install every game except for World Adventures and Late Night. If I go through and install everything ELSE, both those expansion installers will actually begin to work - but then stop when they're nearly finished, and refuse to progress any further. If I try to install either of them right after the Sims 3 base game, it won't bother installing at all. It just stays stuck at 0 files out of 'whatever'.

I saw the fantastic "Must Read" & "Ultimate Fix" threads and that seemed like the answer to my problems, but it seems that these are all based on installing the Sims games via the internet. That's fine, at this point I don't care and would have no issue doing that....HOWEVER, I'm completely unfamiliar with this sort of thing. I'm laughing at myself over here because I have no clue what the words ".rar" "crack" or "unzip" mean. I've never used anything like that before, so I'm totally lost.

Is there anyone here who could possibly give me a complete step-by-step on how the hell to get this resolved? And I do mean step-by-step...everything from what programs I need to download in order to install all the Sims games/expansions/stuff packs....let's put it this way - pretend you're writing instructions for a 6 year old. I'm just as inexperienced as one when it comes to this sort of thing.

I'm just so pissed...I spent $40 JUST on the Generations game yesterday + $40 for the stuff packs, and it's seeming like it was all a waste. And what's pissing me off even more is that I can't get this to work no matter what I do....and I'm wasting my whole weekend on this.

Sorry to rant. Help, anyone??
Greatly appreciated!

Hmm, did you download the expansions from here and use the mac installation guide on how to install the games and also did you use the specific version of Stuffit expander to extract the .rar file/s?