I found two solutions that both mention that the problems is with a Crystal Report that was still open when Visual Studio was closed. Next when opening the project again the Crystal Report is also opened causing Visual Studio to crash.
The solution mentioned is:
1. Open the solution
2. Close the Crystal Report as quick as possible
3. Close Vistual Studio
After this opening the solution should cause no problem.
And in the future close all Crystal Reports before closing the solution.
Visual Studio 2005 – Crashes Randomly
FIX: VS 2005 crashes randomly when using Crystal Reports
Hope it helps.