Selected Answer
Naga
The code below (and in the attached file) will colour A:E of a row in Sheet1 if the cell below that row but in column A is clicked. I've added comments to the code so you can understand how it works hopefully (it uses an event macro which is triggered when the selected cell is changed):
Private Sub Worksheet_SelectionChange(ByVal Target As Range)
Dim myColumn As Long
' Do nothing unless a cell in A was picked, row 2 or below
If Target.Row = 1 Or Intersect(Target, Range("A:A")) Is Nothing Then Exit Sub
' Loop through A:E above cell and do nothing if any has no value
For myColumn = 1 To 5
If Cells(Target.Row - 1, myColumn).Value = "" Then Exit Sub
Next myColumn
'If all complete above, colour the cells green
Target.Offset(-1, 0).Resize(1, 5).Interior.Color = vbGreen
End Sub
Hope this is what you wanted (and in future, please try to provide full questions).
Note that vBGreen is one of a few "Color constants" in VBA, you can't just change the Green bit for any colour but using the .ColorIndex property instead of .Color would give you a choice of 57 colours. You could also change the last line of the code to read:
Target.Offset(-1, 0).Resize(1, 5).Interior.Color = RGB(0,255,255)
to set RGB colours (and adjust the Red, Green and Blue numbers to get very many colours). The 3 bold numbers stated above would give cyan for example.
Hope this helps.