IF [Parameter Name] = "All" or [F] <= INT([Parameter Name]) then 1 else 0 END
Put that on your filter shelf and select for value = 1.
Make the parameter a text field. Have the specific numbers you want as choices, and have "All" as your last choice. (You could also make it an integer parameter, and have display values that are string, but for the "All" display value the internal integer value could be something like a million. And then in that case you wouldn't need the first half of the IF syntax I gave. You'd just need the <= comparison.)
Thanks!! It works like a charm!!!!!!!!