How can I change the format information is presented when I use a lookup field? To be more specific, if I relate a contact to an event with a lookup field, and I click on the magnifying glass icon to look for my contact, how can I show all contacts instead of just recently used?
This functionality is not supported. It will always show the Recently Viewed with the ability to filter the entire set, but it will never just show all contacts. Unfortunately, it just can't be done using the standard lookup field.