Sub flRows()
Dim Rng As Range
Dim fRow&, lRow&
Set Rng = Range("$F$11:$H$14,$J$7:$L$11,$B$16:$D$20,$H$24:$I$29,$C$4:$D$7")
For I = 1 To Rng.Areas.Count
    If fRow <> Empty Then
        If Rng.Areas(I).Rows(1).Row < fRow Then fRow = Rng.Areas(I).Rows(1).Row
    Else
       fRow = Rng.Areas(I).Rows(1).Row
    End If
    If lRow <> Empty Then
        If Rng.Areas(I).Rows(Rng.Areas(I).Rows.Count).Row > lRow Then lRow = Rng.Areas(I).Rows(Rng.Areas(I).Rows.Count).Row
    Else
       lRow = Rng.Areas(I).Rows(1).Row
    End If
Next
MsgBox "Первая строка - " & fRow & vbCrLf & _
        "Последняя строка - " & lRow, vbInformation + vbOKOnly
End Sub