I've been out of the music making game for a while (15 years or so). I would like to get a new DAW and I'm not sure how much CPU Power and RAM I need. I've read a lot about this but I'm still confused

Here are my Hardware Options:
Mac Mini 2.5GHz with 8GB RAM
or
Mac Pro Quad Core 2.66GHz and 12GB RAM
What I plan to do:
Recording: guitar, bass and vocals
FX: Mostly Lexicon Reverb plugin and some delays
VSTi: Kontakt only, no virtual synths. I think on using strings, brass, woodwinds and drums/percussion to go with the above real instruments...
I don't plan on making high track counts or use loads of effects...
The interface will be a Metric Halo ULN-2 and I plan to do most projects at 24/96Khz.
What do you guys think, 8GB or 12GB RAM, 2 cores or 4?
If you use one of the 2 Macs mentioned above, I would appreciate if you could give an overall picture of what they can handle (number of tracks, types and number of plugins used, project sampling rate)