Without knowing how fast the 800s are, how hard the workout is supposed to be, and what the workout is trying to accomplish, it's impossible to tell. If you're doing 6x800 w/ 1 minute rest, that sounds like a cruise interval (or critical velocity) workout and 1 minute standing/walking rest is fine. If you want them to be more like 3k pace, maybe do 1:1 standing/walking recovery or jog a 400 real slow, something like that. 7x400 sounds like it could maybe be at mile race pace? In that case it depends what you're trying to accomplish, if you want a hard workout that will be a marker of your fitness, do it with 1 minute standing/walking rest. If you just want to get some work in without going too far into the well, do 2 minute standing/walking rest or just jog another 400.