How do I translate an original Sim family onto another Sim type?

Question

Example: To translate my family and houses from the Sims 2 onto the Sims 2 Pets.

Answer 1

This is valid for the PC Sims, so I guess it will be not much different for the Sims 2 version:

If you have, for example, the Sims version Bustin' Out and then you got the Pets ones, you just install the new version on the game and the game itself updates the families and everything.
But I know people who told me when they did that everything disappeared and they lost all the families and stuff.

To be on the safe side do this:
Go to the Sims Folder and find the UserData Folder, inside you have several Userdata files with different numbers (each one is a different neighborhood) so it contains every single house and family in that neighborhood. Copy all the UserData Folder contents (all those userdata with numbers folders) and after installing the new version go to the "New" UserData folder and paste the files you got.
You have your families back! :)

Note: if you downloaded any new objects or cloths or head and skins you have to put them also in the Head and skins, objects folders of the new version. If not you are all set to go!

Hope it helped. If it doesn't got to the Sims page and see their Q&A, maybe they have something there.
http://thesims2.ea.com/