I lift 4x a week, an hour at a time, in a split routine. 3-4 one-hour lifting sessions is about right for most folks. Use a split rather than a whole-body routine. You can train two days in a row, just as long as you're hitting different muscle groups.

I have yet to pay attention to my heartrate. If I'm doing lower intensity stuff, if I can barely talk, I figure I'm fine. Other than recreational stuff (bike rides, walking) I mostly do intervals now, and I feel like I'm gonna puke at the end, but it's only for 6-8 minutes and I'm done. Other than a recreational walk, I don't do ANY steady state cardio on purpose.