Re: I am using windows vista on a pc. how do i use photoshop elements to increase resolution to 1920 on longest side without getting distortion

Not sure that I understand the issue completely. Resolution is a value expressed in px/in.

If you wish to resize in order to post on web, go to File>Save for web, enter 1920 on the long side. Be sure that "constrain proportion" is checked.

Let us know if that works for you.