Confused about sims 3 requirements

Hello,
i recently got the sims 3.
i loaded it on to my computer while playing it for a while my screen went all funny, it split my screen into two sides and went black and increased the mouse pointer. then another time my screen went all pixalited and weird colours.
when i looked at the requirements i only look at the ram (whoops) the requirments are:

FOR WINDOWS XP
•2.0 GHz P4 processor or equivalent
•1 GB RAM
•128 MB Video Card with support for Pixel Shader 2.0
•The latest version of DirectX 9.0c
•Microsoft Windows XP Service Pack 2
•At least 6.1 GB of hard drive space with at least 1 GB of additional space for custom content and saved games

and i have
>INTEL(R)PENTIUM(R) M PROCESSOR 1.86GHZ
>1 gb ram
>microsoft windows XP professional verision 2002 service pack 3
>334 MHz
>and 44.9gb free space
> and are currently downloading directX 9.0c

As you can tell i dont no much about stuff like this can you please tell me what else i need or what the problem is i really want to play it so anything will help

thank you :)