Question
can you suggest a tall (4-5 feet)tree-like plant
that will do well close to sunny window but also near air vent (ikeep vent closed) and house is dry despite use of humidifier.  thanks very much

Answer
Hi Torie
You can try a Ficus Benjamina, aka Weeping Fig as long as there is no air coming from that vent.  They like the dryer environment and do well in a sunny window, again, as long as the hot sun is not directly on the plant.  Air coming from that vent may cause the ficus to drop leaves.
I am not sure what style of a plant you are looking for, but a couple of good, easy care plants are
*Chinese Evergreen (may not be tall enough for you though)
*Spathiphyllum aka Peace Lily-One that is in a 10" pot is usually 3-4 feet tall.  You will need to watch the water-it may need quite a bit if it is warm in the corner.  This plant will begin to look droopy when it needs water but will bounce back when you water it.
*Sansevieria-will tolerate any type of living conditions.

Good Luck Torie-
Leslie