I would select paint instead. If you must do wallpaper, I'd select something simple such as a grasscloth.

The options are endless. I am a huge fan of wallpaper in entries, stairwells, hallways and powder rooms. It can turn a transitional space into a real design element of a home. Depending on your location, you might be able to find a store that just sells wallpaper. The larger cities usually have a few in the design districts. In small towns, sherwin Williams usually has a pretty good selection of books. Here are some inspiration photos.

I really like wallpaper in a powder room, but for the huge area of a 2 story entry hall, I am concerned about the cost, resale value, or the cost of replacing or removing the wallpaper.
If you have an unlimited budget, go for it!