Assuming you are erase and installing Tiger from the correct prebundled discs, see this article:
If after quitting the installer with command-Q you can still get to the Finder to view Disc 2, some installers may run straight from the Finder.
If nothing appears to work there, check if your PRAM battery needs replacing. It might, if it hasn't been replaced in the last 4 years, and you don't have an iBook.
Note disc 2 is important for printer drivers, iLife, and on iBook G4s, Mac Mini G4s, and iMac G5s for Appleworks, and certain games and prebundled software not normally found on the operating system. PowerMac G5s, iBook G4s, Mac Mini G4s, and iMac G5s may also have Classic installer on disc 2. iLife versions prebundled, and minimum system requirements for iLife can be found on this user tip:
Printer drivers normally available on the most recent operating systems, are found on this article: