You can set reference (Project|References...) to "Microsoft Scripting Runtime" and use code like this:

Dim FSO As Scripting.FileSystemObject
Dim FileStream As Scripting.TextStream
Dim FileContent As String
Dim StartPosition As Long
Dim EndPosition As Long
Dim LineContents As String

  Set FSO = New Scripting.FileSystemObject
  Set FileStream = FSO.OpenTextFile("C:\WINNT\SYSTEM32\DRIVERS\etc\Services")
  FileContent = FileStream.ReadAll
  StartPosition = InStr(1, FileContent, "van52", vbBinaryCompare)
  If StartPosition > 0 Then  'Line is founded
    EndPosition = InStr(StartPosition, FileContent, vbCr, vbBinaryCompare)
    LineContents = Mid(FileContent, StartPosition, EndPosition - StartPosition)
  End If
  FileStream.Close
  Set FileStream = Nothing
  Set FSO = Nothing

After this, extract number from founded line.