DPI

What is a good standard dpi and pixel by pixel for printing an 8x10?

Most pro labs are going to print around 300 dpi. So, a file that's 2400x3000 is just right.

I've found 250ppi to be sufficient.
If you're printing at a lab, they should be able to advise you.
If you're printing yourself, choose a resolution that works (probably 250-300). Remember, there's no advantage to excessively high resolution - it just needs to be high enough for pixels to be indistinguishable to the human eye. To be honest, 150 is probably enough (but I'm sure lots of people will disagree with me...)

Thanks for the help.