You need to do several things in order to get this to work (and to have it make any sense).
To start with, C:Temp is not a valid folder location. If you're looking to start in the Temp folder located off the root of drive C:, the correct path is C:\Temp (note the backslash).
Next, Cursor Files do not end in .txt, and you can't display the contents of a Cursor File in a TextBox, because it is a text box, not a cursor box.
(And just to make sure you know: All of the things you're setting in your code for the OpenFileDialog, like Title, Filter, and InitialDirectory can be set at designtime using the Properties window in the Visual Studio IDE. If they're always going to be the same values, set them there instead and remove the code.)
Adding those fixes, and some code to actually load the file if one is selected (and not try to do so if the user cancelled), we can do something like this (tested in VS2012, as I don't have 2010 installed any longer on this box):
Private Sub OpenToolStripMenuItem_Click(ByVal sender As System.Object, _
ByVal e As System.EventArgs) Handles OpenToolStripMenuItem.Click
OpenFileDialog1.Title = "Please Select a File"
OpenFileDialog1.Filter = "Text Files|*.txt"
OpenFileDialog1.InitialDirectory = "C:\Temp"
If OpenFileDialog1.ShowDialog() = DialogResult.OK Then
Using sr As New System.IO.StreamReader(OpenFileDialog1.FileName)
TextBox1.Text = sr.ReadToEnd
Catch e As Exception
Hey, thank you all for the help, i have added the \ and changed from cursor to text, i did try the code you gave me but the "catch e as exception" line gave me an issue "variable e hides a variable in an enclosing block"