i have changed an old vb6 application to 2005.net and i want to know if this sub (which does work) could be better, by that i mean have i used the right functions ?, are there better(faster) ones ?

this removes a username and every line under it until it reaches another username.
VB Code:
  1. Public Sub RemoveUser(ByVal StringUser As String)
  2.         Dim sr As New IO.StreamReader("C:\usernamesinfo.txt")
  3.         Dim sw As New IO.StreamWriter("C:\usernamesinfo2.txt", True)
  4.         Dim Found As Boolean, Lines As String
  5.  
  6.         Do While sr.Peek >= 0
  7.             Lines = sr.ReadLine
  8.  
  9.             If Found = False Then
  10.                 If InStr(Lines, "USERNAME" & StringUser) = 0 Then
  11.                     sw.WriteLine(Lines)
  12.                 Else
  13.                     Found = True
  14.                 End If
  15.             Else
  16.                 If InStr(Lines, "USERNAME") > 0 Then
  17.                     Found = False
  18.                     sw.WriteLine(Lines)
  19.                 End If
  20.             End If
  21.         Loop
  22.         sr.Close()
  23.         sw.Close()
  24.         IO.File.Delete("C:\usernamesinfo.txt")
  25.         IO.File.Move("C:\usernamesinfo2.txt", "C:\usernamesinfo.txt")
  26.  
  27.     End Sub

thanks.