Cambiar color de fila al pasar el puntero del mouse en un datagridview

[eperedo]

Podría ser usando los eventos CellMouseEnter y CellMouseLeave.

Código vb.net:

Private Sub DataGridView1_CellMouseEnter(ByVal sender As System.Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles DataGridView1.CellMouseEnter
        If e.RowIndex >= 0 Then
            Me.DataGridView1.Rows(e.RowIndex).DefaultCellStyle.BackColor = Color.Aqua
        End If
 
    End Sub
 
    Private Sub DataGridView1_CellMouseLeave(ByVal sender As System.Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles DataGridView1.CellMouseLeave
        If e.RowIndex >= 0 Then
            Me.DataGridView1.Rows(e.RowIndex).DefaultCellStyle.BackColor = Color.White
        End If
    End Sub
 

Espero te sirva