Only able to play Mansions and Gardens

I just installed the Sims 2 Ultimate Collection off of Origin using the free product key. When I go to start up the game and get past the intro sequence, all I see is a screen for "Sims 2 Fun with Pets" with music playing, and nothing to click on or indication that I can start up the game. To exit out of the game, I've had to restart my computer. 

Most recently, after the Fun with Pets screen, I was taken to a screen for "Mansion and Garden Stuff" and I was able to look pick through neighborhoods. I didn't pick one/start up the game because I'm confused:

How the heck do I navigate this game? Where are all the expansions and other "stuff' packages that are supposedly included? How do I get to them? Or am I just completely misunderstanding how it all works.

Thanks.

Like this: http://answers.ea.com/t5/The-Sims-2/INFORMATION-REQUEST-No-Neighborhoods-to-pick-from/td-p/3156388 ?

Could this be your issue ?

The fun with pets screen and Gardens & Mansion part is normal

I think the poster is referring to this problem:

http://answers.ea.com/t5/The-Sims-2/All-I-got-was-Mansions-and-Gardens/m-p/3200253/highlight/true#M5057

If you are new to the Sims and you download the Ultimate Collection, it dumps you into the Mansions and Gardens screen when  it starts up, with no clue how to get to the main program.   

This helped: "It'll come up like that because that was the last game released. It is the Sims 2 Ultimate Collection, it's just not called that. Everything is there. 

You can create your own sims - just go to Create-A-Family in the family tab in the neigbourhood menu (once you've loaded a neighbourhood)"