ACT! is functioning as designed.
When you click the browse button at a phone field, the Enter Phone Number dialog box appears.
Click the Edit Formats button. The Edit Phone Formats dialog box appears.
The phone format that is displayed is dependent upon the Country field for that contact. If you have never added phone formats for contacts from a specific Country, the only available Format will be Free Form. If you add Phone Formats to this field, all contact records using the same Country code will have those format options available.