Anuska, I know why your computer loves you so much:
And atm I am not having any antivirus installed
An antivirus programm can be heavy to handle, so in a way it helps a lot when you don't have one (I wouldn't advise this though!)
I do the regular maintainance of both system (with Glady Utilities) and hardware by vacuuming it lol but other than that I do nothing special
This is very important, many people forget this
except for calling my PC with a name and occasionally cheering for it to do something right
But this is by far most the thing we should all do!!!
Now a little more serious...
If you have a choice when buying a computer for instance, I would also recommend 8 GB. But be ware that you'll always get less good use out of a laptop then a desktop, so on average a laptop needs a little more GB then a desktop to perform the same way. But 8 GB should be enough.
With every EP and SP the game gets bigger. After SN the game got too big for my laptop with 4 GB. I am really wondering how much more EP's and SP's EA thinks we should be able to have in 1 game...
All this extra additions to a game can get a little messy I imagine. There is a reason why so many of use (and more each day) use mods. It's really a shame actually that there are so many problems with such an expensive game. But that's for another thread
PlatnumDymnd, I think I read that you just bought a new laptop, so buying one with 8 GB won't be an option. What also matters is how much bit is your system, 32 bit or 64 bit? A 32 bit system is limited to using only 2 GB. Therefor you need a 64 bit system for The Sims 3. This is something you can change by building up your laptop from zero again, but you can also do some adjustments on a 32bit system. NRaas explains this on his website. I am not sure if I am allowed to place a link, since that website is all about mods. (look in Game faqs, General issues)
Win7 is a good operating system, because it is less demanding then Vista.
Of course it also matters what kind of processor you have. Maybe it has trouble loading the game because of that? You say it freezes. But how long do you wait? I have to wait for 10 minutes sometimes. If another world isn't the problem, then it could be UC is too much foor your system right now. I doubt it is your sims, since you don't use cc. Have you built a very big house maybe? That could be the problem. Or no house at all? It can help if you have a small house then, so the game can load easier (maybe it has to know where the sim should go to on the lot). The neighbourhood has some very beautiful but huge houses. You could delete 1 or 2 and see if it helps.
You see, there are many things you can try. It just takes a lot of time, unfortunately
Oh, btw I have a desktop 16 GB RAM, Intel Core 2 Quad CPU Q9400 2,66 GHz 64bit with Win7 (but I just got it and I didn't want to have to do that again soon
)