I just re-installed today but I forgot to do the limit adjuster thing, so I dunno if it is really necessary. If the game freezes halfway, then did you install the cracked gtavc.exe for Nitzkit World? I had the same problem too but it was fixed after I got it. There was this thing that Flippa posted that helped me too before. I think he has XP but it is pretty much the same for any OS to follow.

1. Click Start
2. Select Control Panel
3. Select System
4. Click the Advanced tab
5. In the Performance region select Settings
6. Click the Data Execute tab in the dialog box that opens
7. Select Turn on DEP for all programs and services except for those I select
8. Click Add.
9. The open dialog box will open. Browse and select your application.

Restart after you've added.
[this did not worked ]