Before you restore an application from a Time Machine backup it would be wiser to remove the current installed copy then reinstall from the application's original distribution medium - download, CD/DVD, etc. The reason for this is that Time Machine backs up every hour. By now the bad version of this application is now backed up to your Time Machine backup drive. Restoring from the backup won't resolve your problem.
First, uninstall the old program. If the program came with an uninstaller then use it. If not then start by deleting the application from the Applications folder. Then locate all the support files associated with the application and remove them, too. Look for these in:
/Users/yourusername/Library/Preferences
/Users/yourusername/Library/Applications Support
Applications may come with a separate uninstaller program that could also be in your Applications folder. Some applications may install other files in other locations on your computer. If you tell us what the application is we may be able to provide additional help.
You may find more information here:
The XLab FAQs. Read the FAQ on uninstalling software.