Ubuntu 8.10 doesn't appear in my MacBook?
 

I installed Ubuntu 8.10 in my MacBook and become default operating system. I want Mac OS X is the default operating system. So I restart my Mac using System Preferences/Startup Disk. When I want to restart back to Ubuntu 8.10, it seems that it doesn't appear in my machine. Unless I restart it with the CD in it. Even my Boot Camp disk can't be restored. Should I reformat my Mac?

Welcome to LQ! I would recommend posting in the Laptop forum rather than the newbie one.

I own a macbookpro, and I dual-boot m$ vista and mac os x. Can you reach the boot disk selection screen by holding the alt/option key immediately after powerup? It should not require startup disk selection to choose which partition to book.