Instead of escaping the single tick, I find it more straight forward to use QUOTENAME:

SELECT @Result = 'Total of ' + QUOTENAME(CAST(@NoOfColumns AS VARCHAR), CHAR(39)) + ' column(s)';

I am not sure why are you dropping and recreating the Foreign Keys? Why not just disable and re-eanble them?

If the table has an Identity column, you cannot Truncate...