WHAT VERSION DO I NEED TO USE to open .VBPROJ

I was coding in Visual Basic and had to reload windows operating system.  I lost the VB program I had been using.

I tried to open a .VBPROJ with visual basic 2008 which I thought I had been using and it said that it could not open VBPROJ with this version.

I have very little experience with visual basic but I did write a complex inventory for an MC9060 handheld that I do not want to lose.   WHAT VERSION DO I NEED TO USE? 
Open the vbproj file with NotePad, what does the second line look like?

For VS2008

<Project ToolsVersion="3.5" DefaultTargets="Build" xmlns="http-://schemas.microsoft.-com/developer/msbuild/2003">VS2010

<Project ToolsVersion="4.0" DefaultTargets="Build" xmlns="http-://schemas.microsoft.-com/developer/msbuild/2003">

--------------------------------------------------------------------------------

Please remember to mark the replies as answers if they help and unmark them if they provide no help, this will help others who are looking for solutions to the same or similar problem.