I've found that OS X installs can get a bit "bloated" over the years. Fortunately it's not like Windows, but it can be beneficial to start from a clean install.
If you want to "restore in place" you can choose "archive and install" from the restore disk. Otherwise, what I'd do is wipe the disk, run the restore disk, and then during the initial set-up select "time machine backup" as your source for restoration.