Stictly, iLink is a slight modification of the Firewire Spec. But it's not important, It'll do everything.
I've done a small amount of video editing on a P!!! 800, TNT2, 32MB RAM, 20 GB HDD. Worked fine but full res playback had some very slight stutters occationally.
Your system should cope really well as long as it runs smoothly already.

Adobe Premier is very good, capturing the vision can be a pain compared to consumer stuff. iMovie is great at this. It starts a new clip when the scene changes. That is, when you stopped recording at one point and restarted, it detects the index mark and starts a new clip. I don't know what other packages do this as it's a great time saver. Set your editor to capture and sit back. Premier still requires you to mark out the regions you want captured. You can create a batch to get them but it adds about triple the amount of time you want to capture.
I don't know which packages, if any, have the auto-capture function of iMovie. (Anyone?)

Having all your images on a separate disk is good if you can take advantage of bus speeds and so-on. Mostly, you should be fine though.

Video editing is really rewarding though. Have fun with it!