>I got the idea to make a standing rib roast for the holidays.
>Also, about how many pounds should I get for two people? If cooking a larger roast is preferable I don't mind leftovers.

If it's all about presentation and feeling like you've cooked a big
fancy piece of meat, than by all means purchase a 3-rib roast.
If on the other hand you just want a delicious piece of beef to share
with your "significant other" (or whomever), you can greatly reduce the
amount of hassle by having your/a butcher cut you a single bone
rib-steak which can easily come in weighing at over 2 lbs. if you
request a big 'un.
With an oven-friendly (not non-stick) skillet you can pan-sear it on
the stovetop on very high heat and pop it in a 450° oven to finish.
Using the very well advised instant read thermometer, you can pull it
out when cooked to your liking.
No 4-hour cook time and a great piece of meat to share... regardless
of which cut you use, be sure to allow the meat to rest lightly covered
with foil to allow the juices to redistribute. Make a nice pan sauce
while you wait. Kev