Should I replace the logic board???

I have loved my 12inch PowerBook G4 - but it's 5 years old now and the both the logic board and the DVD drive need replacing. I am willing to spend the money to fix it - but I don't know if this is the beginning of the end.... I love macs, but can't afford a new one right now..... does anyone have any thoughts as to whether I should hold out and save for a new one or just fix the logic board and hope something else major doesn't go soon. Thanks!