Thankfully, I think the Internet was created for just this kind of problem. I recently read a post at Such the Spot, in which Darcie provides a nice, easy-to-reference list of 10 house plants that can improve your home.
The post Ten House Plants That Will Improve Your Home includes plants that disperse airborne toxins, decrease dust and mold, and reduce stress (among other things) like English Ivy and African Violet. However, you should definitely check out the rest.
With a list like this, I can fill my house with pretty plants and then convince people I knew what I was buying and why. Although I'll have to convince strangers. Anyone who knows me will be suspicious.
What's your favorite house plant?