It totally depends on the album or project.  In Metal, 2 tracks and 4 tracks are both pretty common.  For super-technical, fast stuff, 2 is more likely just because of how difficult it would be to get 4 tracks that tight.  On Mirror of Souls, there are 4 tracks of rhythm guitars; two on each side, one pair with the Krankenstein and one pair with the 6505+.
Kick drum EQ just totally depends on the sound you're starting with and what you want to achieve.  In general, kicks will have a lot of muddy low-mid buildup, so I'll almost always pull some frequencies out somewhere between 250-500HZ.  I usually sit the low end of kicks down around 65 HZ or so, and sometimes I'll add some more EQ up top if I need more slap or attack to the sound.  Beater attack usually happens anywhere between 2.5-4.5 kHZ (even up to 6 kHZ sometimes).  Finally, I sometimes add a little air way up top around 10 HZ or so.
But again, no rules--just depends on the sound I'm starting with and what it needs to sound like in the end.