I have 2 photos I submitted for a calendar contest, and for the pics to make it as a full page image they had minimum requirements that weren't met. Pics need to be at least 2300 x 1800 pixels at 200dpi.  I can resubmit before publishing, so need to know the following:

1) One pic is okay at 2611 x 1958, but need to increase dpi from 96 to 200.

2) Other pic is only 976 x 1632 at 72dpi, so need to increase pixels as well as resolution.

Is it possible to make these changes in Windows photo gallery without distorting the picture too much? If not, where can these types of changes be made?