usb enclosures and formating the hard drive ?

it's a long shot, as i'm sure people are just wanting to laze about this boxing day eve :) need some advice on formatting a hard drive to go in my usb enclosure.i think i've got it sussed but would like some confirmation i'm doing it right.

1. go to administrative tools
2. double click computer management
3. disk management
4. right click on "said drive" and click "new simple volume"
5. click next and next.....and this is where i'm upto

confronted with 3 choices
1. assign the following drive letter
2. mount in the following empty ntfs folder
3. do not assign a drive letter or drive path

now i'm thinking select the 3rd option as it's going to be a removable drivebut i'm not sure...any help greatly appreciated :)