excel vba select range of row with numbers only

In statements like this:

dim ws as worksheet
ws = ThisWorkbook.worksheets(1)

ws .Rows([range of rows]).AutoFit

or

Set myRange =  ws .Rows([range of rows]).EntireRow

how might I specify the [range of rows] using just numbers, instead of the string "R1C4" type construct?

That is, something like this:  

ws.range(ws.cells(1,1),ws.cells(500,1).EntireRow

which executes, but then this:

ws.range(ws.cells(1,1),ws.cells(500,1).EntireRow.Select

fails with "Select method of range failed", so I can't verify if I really have the range of rows I want in r1.

Any suggestions on this would be appreciated.

Thanks!