GTA III PC version issues

I haven't played GTA III in a while, so I thought I'd give it a go.
But when I started it up, it was all choppy and very slow....
I thought maybe my PC specs were too low. This is what I foundMinimum System Requirements * Pentium III 450MHZ
* 64MB RAM
* 16MB Direct3D Graphics Card
* Directx Compatable Sound Card
* 8X CDROM
* 500MB Free Hard Drive Space
* Win 98/ME/NT/2000/XP
* Directx 8.1 or newerRecommended System Requirements * 700MHZ CPU
* 128MB RAM
* 32MB Direct3D Graphics Card
* Directx Compatable Sound Card
* 8X CDROM
* 500MB Free Hard Drive Space
* Win 98/ME/NT/2000/XP
* Directx 8.1 or newerHere's what my PC currently has:
Pentium III 700MHZ
320MB ram
32MB Direct3D
DirectX 9.0c
12.4GB HDD remaining
Windows XP Home EditionAs you can see, my PC does meet the recommended requirements, and exceeds a few, so there should be no reason why it's all choppy and slow.
any help on this would be great!

you don't have enough ram for windows XP to run properly, and I'd also try defragging your hard disk.

Just defragged yesterday... didn't know about the ram thing though, everything else seems to work fine, just GTA is kinda off