If your post has no typo's, no, you do not have the minimum required.
I've never heard ov a video card with 18MB - do you mean 128MB?
Here are the minimum specs required to play the game:
-Operating System: Windows 98/2000/ME/XP
-Processor: 1GHz or greater
-RAM: 512 MB
-Video Card: DirectX 9 compatible. Pixel shader and vertex shader compatible hardware with 64 MB of texture memory
-Sound Card: DirectSound compatible audio hardware
Now those are the bare minimum. To get much better performance, you'll want to get:
Processor: 2GHZ or better
RAM: 1GB (try to get 2GB)
Video Card: 256MB