I'm so frustrating about Sims 2 vs Sims 3!

[sanx]

I was a Sims 2 player and I got many expansion packs but I lost my Sims 2 basic installation Disc.

So I decided to go for Sims 3 just a few weeks ago, I like the features that there are more details of the Sims' personality, better graphics and lifetime rewards.

However I have a huge problem with Sims 3 because the game freeze all the time.
Averagely it takes 15-20 mins to load the game. If I play in a huge lot, the game lag like crazy, every second becomes every 2or3 seconds......

Everything is slow motion in my Sims 3, I have a hard time to let my Sims to try out everything in the game.
my laptop is not bad for gaming and it was a pretty new one with Window 7.

I am thinking to upgrade my video card for my laptop but I heard is hard and risky to do.

So..... i started missing my Sims 2... Seasons, University, Business, Nightlife, etc.
There are more CC for Sims 2 and the most important thing, IT WORKS!

So i'm frustrating about buying the Sims2 installation pack again OR upgrade my video card for Sims3 ??

For those who played both Sims 2 and Sims 3, please give me some comments!

Thank you!!!!