Well, a remote diagnosis is difficult if I don't even see what's happening (or not happening).
I did not expect that opening the Toast from Terminal would work; but it's sometimes shows error messages that are otherwise invisible, like reports about missing files. (I once had a problem with iPhoto 08 on a machine, and trying to launch it with the open command actually did return reports of what files the program could not load and where it was looking for them.)
PDFs: Open Finder, select a PDF file and press Command-I (or right click on the file and click 'Get Info'). In the info window, there is a section named 'Open with' where you can choose an application. If you select 'other app...' and change the filter to 'all applications', you can change the default app to any program you like. If you check the 'change for all' checkbox, all PDFs will by default be opened with the selected program. The Preview application is in /Applications. Changing the app here should also change the behavior of the web browser.
There is a ridiculous workaround #1 for Macs that you should always try --before-- you actually scratch your hard disk and re-install. Boot the OS X installation DVD and launch the Disk Utility from there, then let it check and repair all file permissions. When it's done, reboot and check if it makes a difference. The funny thing is, it quite often helps.
But if everything fails: Save your data, format the system hard disk and install a clean operating system. Don't we all just love doing that?
And remember: It's a Mac and it 'just works'... ;-)
I did not expect that opening the Toast from Terminal would work; but it's sometimes shows error messages that are otherwise invisible, like reports about missing files. (I once had a problem with iPhoto 08 on a machine, and trying to launch it with the open command actually did return reports of what files the program could not load and where it was looking for them.)
PDFs: Open Finder, select a PDF file and press Command-I (or right click on the file and click 'Get Info'). In the info window, there is a section named 'Open with' where you can choose an application. If you select 'other app...' and change the filter to 'all applications', you can change the default app to any program you like. If you check the 'change for all' checkbox, all PDFs will by default be opened with the selected program. The Preview application is in /Applications. Changing the app here should also change the behavior of the web browser.
There is a ridiculous workaround #1 for Macs that you should always try --before-- you actually scratch your hard disk and re-install. Boot the OS X installation DVD and launch the Disk Utility from there, then let it check and repair all file permissions. When it's done, reboot and check if it makes a difference. The funny thing is, it quite often helps.
But if everything fails: Save your data, format the system hard disk and install a clean operating system. Don't we all just love doing that?
And remember: It's a Mac and it 'just works'... ;-)