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I'm assuming you mean whole finger ribs, not cross-cut or anything like that. I like to marinade my beefies in a mixture of beer, worcesteshire sauce, a bit of lime juice, a little salt pepper and whatever other spices you like. Leave them in a bag for 2-4 hours in the fridge and make sure you agitate em and flip the bag every :30 or so.
As far as smoking the goes, use 225-250. I personally don't foil them. They can be tricky and may take up to 7 hours! But dang, they're worth it. Hit 'em with mesquite smoke - can't go wrong.
If you haven't done beef ribs before, let me remind you to remove the membrane on the back of the rack. I don't marinade mine. I just apply a rub of my chosing. The temps and time estimate you've been given is good. Remember the time is an estimate. It could be done sooner or later than the 5 hrs. The best way to tell they are done is when the meat starts pulling away from the bone. Take a look at Toms' post and/or other previous posts and you'll see what to look for.