The disk capacity for my VM which is used as a development environment for Sharepoint 2013

I want to set up my development environment for sharepoint 2013 on a VM; my environment specification are as follow:-

• A laptop with windows 7 professional 64x

• The laptop has 670 GB harddisk

• 32 GB of RAM

• VM workstation

During my creation for a new VM I mount an ISO image representing a windows server 2008 data centre to the VM , but it ask me to provide the following:-

1. Specify the disk capacity , by default it select 40 GB , **so should I modify this number**?

2. Then I have to select between these two options ; Store virtual disk as a single file OR to split virtual disk to multiple files. **So which option I should use**?

Thanks for you e help