When you create a new document a 300 dpi and then bring in a photo, it will automatically be put in at 300 dpi. The photo may appear much smaller than you thought it would be depending on your cameras resolution or the resolution you scanned the photo at. If you enlarge a photo too much you'll see it get pixelated or its quality will generally degrade (odd artifacts etc). I try not to enlarge my photos too much do to this issue.
Sorry I'm not sure about changing text colors in PSP.

I don't use that program. In other programs there's a little color swatch that appears when you open the text tool. If you change the color in this swatch, the text color changes. That's really general info but maybe it will help.
