Advice for update to system...?

[Clarke]

Hi,

I must start by saying that I'm not the most technically minded of people but am about to update my system with a budget of £7000.

I feel that I need more 'voices' so will be going up to HD2 (I'm currently only using HD1) but also, i certainly need to be able run more RTAS plug ins than I'm currently able to do so with my MacG5 (2.5GHz) before is has a fit!

I suppose my questions are this:

What spec powerMac - i think it's important to go up to 64bit and for £4500 what's the best combination of processor and Ram spec I should aim for (assuming on a 1TB hard drive as standard)?
I'm currently using Protools 8 - do I need to upgrade to Protools9?

All thoughts and opinions will be much appreciated.

Thanks,

Clarke.