When calculating the list, try a calculation field that combines the two fields and places a specific number of spaces between the words based on the length of the first word. If the first word will have a maximum length of 10 characters the use 15 as a position for the second field. So an entry like "Internet" having 8 characters would have 15-8 or 6 spaces calculated. With this calc you can select a mono spaced font for the drop down list and everything will like up as you propose. If you do not use a mono spaced font it will not work.
If you are using FileMaker 13, use a portal instead of a drop down list where clicking a portal row selects the value in that portal row. Place that portal row inside a popover. This then allows you to get your values to be properly organized in columns.
Looks like padding the field will be the easiest solution. I think long term the portal option may be best but I was not sure how to insert the selected data into the field.
Thanks for the information.
Select the fields in the portal row and use Button Setup to turn them into a button.
Have the button perform this script:
Set Field [YourTable::YourFieldForThisValue ; PortalTable::FieldToCopyToTheField ]
The mouse click on the portal row selects that portal row and sets that as the context for this set field step to then refer to data from this portal row.