Converting Time To Seconds.

I have the below macro. It is used to translate time to seconds (i.e. 0:20:04 minutes to 1204 seconds)
This works well, but i just want to know 3 things.
First, can the new data (seconds value) be added to new worksheet (worksheet 4) of the workbook the original data is taken from, instead of a whole new workbook?
Second, can this be done without having to save the original workbook first?
Third, (Im sorry i know this is VERY simple) but this macro is part of a larger macro, and i just want to know the code to hide the screen updating as the macro is running.

Sub Refresh()
Columns("A:A").EntireColumn.Select
Application.CutCopyMode = False
Selection.TextToColumns Destination:=ActiveCell, DataType:=xlFixedWidth, _
FieldInfo:=Array(0, 4), TrailingMinusNumbers:=True
End Sub.........