The first one will take you to cell A10 if you put it on the This Workbook:
Sub Workbook_Open()
Application.Goto Reference:="Sheet1!RC"
End Sub
Put this one on the worksheet.
Sub GtRng()
Range("A1:D10").Select
End Sub
Anytime you select a range, then do your entry, it will remain within your range, whether you hit enter or tab, until you click outside of that range.