OK mate, read these books:

Creative Recording 1: Effects & Processors; Paul White
Modern Recording Techniques; Huber & Runstein

You'll go through a lot of stuff thinking 'I don't need to know this sh*t!' but you'll LOVE me for it in about two months when you get through them and work it all out.

As for the rest, processor time refers to how hard your machine is working. The more proc. time used, the harder your machine works. When it gets too much, your machine will fall over - you'll get clicks and drop-outs in your audio, your interface will respond sluggishly and things will eventually grind to a halt.

Reverb is the most processor-hungry effect, because of what it's trying to do - re-create the effect of millions of echoes from every point on every surface in a room. (This is why you get 'hall' 'cathedral' and so on settings, and room shapes. 'Plate' refers to a method used to emulate this effect used in pre-digital studios, as does 'spring'.)

Remember, all computer programs used to make music rely on the techniques developed for traditional studios on analogue desks. Knowledge of these techniques means more understanding of what you're doing on your PC.

Good luck mate!

Tequila