I would say ignore Pro Tools.. It used to be the only software you should use for recording, but if you are used to Cubase, then Cubase is the way to go. IMHO Cubase is a lot friendlier than Pro Tools. I'm biased as I've been a long time Cubase user and I've had lots of problems with Pro Tools. Its more hassle than its worth. I also believe Cubase is more user friendly than Logic, but thats because I always use Cubase. I had to use Logic in one of the studios where I work and it took me 30 minutes to work out how to use a Virtual Instrument. Most of the learning curve is down to different naming in both the packages - you say "Audio Object" i say "Virtual Instrument"
And if you do anything to do with MIDI forget Pro Tools, as its MIDI support is a joke (come on Digi - your on v. 6.7, and still only basic MIDI support!). There are a few things I like about Pro Tools, mostly its hardware. I really like the TDM hardware, as it reduces the strain on your CPU. Also its pretty stable (if you dont use it on a network - the only time a mac has ever fully crashed on me - kernal panic). The other main disadvantage is Pro Tools will only run with a Digidesign Audio Interface (e.g. 002, Mbox), and they are reasonably expensive, although with the exeption of the Mbox are all really nice quality.
So I would recommend Cubase. As for hardware, I'd recommend Firewire interfaces over USB. There arent enough USB2.0 devices yet, and USB1.1 is only really suitable for stereo in, stereo out applications at less than 24bit 96kHz.
I recently got introduced to the MotU Traveller, and thats one of the most impressive external interfaces I've seen in a while. So look at that, and see what you make of it.
How many inputs/outputs do you require? What are you going to be using the DAW for?
As for 2-track editing software, look in to Bias Peak. It seems to be the biggest editor on the Mac platform.. You should be able to get Cool Edit Pro (now called Adobe Audition), which I've always prefered to SoundForge.
Oh from the looks of it you only need 2-in, 2-out. I'd recommend M-Audio hardware as they are outstanding quality for the price. Again though I'd recommend Firewire over USB1.1, better speed so better bandwidth for your audio. USB1.1 wont allow you Full Duplex 24/96 audio, which you may not require but its always nice to have. If you are using 24/96, it might be worth buying a nice fast external drive.
Hope this helps!