i had a similar problem.... what helped was,that i had 10.2 on an external firewire drive ... this was not an apple drive and i think any firewire harddrive will do for you ... i booted the TiBook up with Jaguar and inspected my internal harddrive .... i ended up installing a fresh new Panther on it, after i saved some important info ... the option key during startup is definetely a must - i was wondering if you could (somehow) run the macmini with the screen of the powerbook - but i guess it wouldn't be that easy/without any additional cost ...