To Rip or Not to Rip

Today, I painted the walls in the upstairs hallway. I still need to do the trim and the doors, but I think knowing that there's more to do is always a given. I'm pretty sure I'll never be done. haha

This was a fun part: painting in between the railings on the staircase. Pretty tedious.
Unfortunately, I encountered a snag. I can't decide what to do about the big wall going down the stairs and the small wall at the top landing. If you look closely, you can see that they have wallpaper on them that's been painted over. The whole wall is sort of bumpy and there are obvious seams from the wallpaper edges.

Here's the worst seam. So I painted a patch to see how it would look and if it would hide the bumpiness a little more ... turns out, not really. Now I'm stuck trying to decide whether or not to rip off the wallpaper and see what's underneath.
Sighhh ... I never knew walls could give me so much trouble (ie. the paneling in the dining room that I still don't know what do with).