[microrario]

So I'm trying to format but it only gets as far as the blue screen before the dialog is supposed to appear. The mouse pointer is showing and when I press the space bar it turns into the rainbow wheel, so it's definitely not locking up. I've already tried repairing permission and pram. Anyone have any ideas?

[steve626]

You don't give enough details for anyone to really provide assistance. However, you should check a few things:

1) Does your computer meet the minimum requirements for Tiger?
2) Do you have a DVD drive that has recently read DVDs successfully, and is it working properly as far as you can tell? What are you doing (holding down a key?) to try to boot from the DVD?
3) Can you boot from other CDs or DVDs that are bootable? Examples to try are utilities like Disk Warrior or Tech Tool Pro, and earlier Mac OS CD/DVD such as 10.3 or 10.2 (assuming your computer is compatible with the versions on these CD/DVD). Does you Tiger DVD have a scratch or other blemish?
4) Have you applied all firmware updates to your computer that are available?
5) Is your RAM from a reliable source, or was it a "bargain" (some inexpensive RAM does not work well with Tiger even if it worked with earlier systems)?
6) Were you having any issues (hardware or software) before this?
7) What computer are you using, model, speed, amount of RAM and disk space, free disk space? Is the Tiger DVD either a "universal install 10.4 DVD" or is it one that is meant to be used with your specific model and make of Mac?