uninstalling an expansion and installing a new one [SOLVED]

hello.

i would like to uninstall pets and then install late night. if i uninstall an expansion pack, i will still have my families and houses right? but if i install a new expansion, will those things be gone?

because i don't want to lose a house that i made by myself which took for hours and i like that house. i hope i will get the solution. thank you.    

i have generation, seasons, ambitions, university, supernatural and pets. and i have free space on my local disk c for about 35.3gb. and late night is 6.29gb. so i'm afraid i will my game will lag, not responding or shut down by itself.

because last two days, while i was saving the game after hours of playing, the saving went on for an hour. so i assumed it's not responding. last night, while my sister was playing, the game shut down and said 'the sims 3 has stopped working' out of the blue.

and i find late night is interesting. and i seldom make pets because i can't seem to manage everything in the game like the career, degree and pets.

//EDIT: and how do i uninstall it? i had done this once before and i just went to the control panel and uninstall an expansion from there. is that the correct way?

oh. my bad! sorry! hoho.

ok thank you.  

sorry for the late reply! yes, it works. thank u!