Can anyone tell me what the best PC specifications are for using all of Pinnacle Studio 12 Ultimate's features without any lag, and with fast processing times?

Pinnacle recommends the follwing specs:
-Processor: Intel® Core™2 Quad 2.66 GHz
-Graphics Card: 512MB Dedicated
-RAM: 2GB
-OS: Windows XP Home

I've been using a PC with the following specs:
-Processor: Intel Core 2 Duo 2.00GHz
-Graphics Card: Nvidia GeForce Go 7900 GS
-RAM: 2GB
-OS: Windows XP or Vista
The latest Norton security runs at the same time (even though I am not online whilst editing I have no control over Norton), it is the only other program running at the same time as Pinnacle.

I edit AVCHD format video (1080*1920 pixels) from a Panasonic HDC-SX5 camcorder (raw video is in .MTS format) and I make sure the all the raw video being used is in the same folder on the harddisk.

My computer can create the AVCHD video (very slowly), but is not powerful enough to properly edit it taking full advantage of the software.
Thankyou in advance