Picture Monkey, can you advise me please?

I used to like using picture monkey but when it came to where I wanted to enlarge images to hang on my wall i found I could only go as big as 8x6" before the pixles started showing. This was because the programme had compressed the image which was very annoying.

is there any way I could still use it and save a copy and still keep the original at it's proper 300 dpi and size without picture monkey shrinking it to death?

Thanks.

Never used it before, but just had a look and saw this which may help http://www.picmonkey.com/help/articles/633730-standard-photo-print-size

Thanks very much