Virtual Domain Controller - Sizing and Partitioning

I am planning on deploying several virtual domain controllers (250 users).

The DCs will be Server 2012 VMs (2GB RAM) running on Hyper-V.

I was simply going to install the operating system and AD on a single virtual hard disk, single volume - C:\

Now I am not so sure and would like some guidance.

1. 1. Should I split System Page, NTDS, SYSVOL etc.?
2. 2. If I do split them should I split them onto separate virtual hard disks, or simply separate volumes (on a single virtual hard disk)
3. 3. How should I size it?

I was thinking :-

C:\ System and Page (40GB - Page file will be set to 3GB i.e. 1.5 x RAM)

E:\ NTDS, SYSVOL,  Logs (40GB total)

DHCP and DNS will also be installed on these DCs.