CSS:
Code:
postbody > a {
  color: #0044BB; /* or whatever */
}
THAT'S ALL you need in the style sheet! Now, if you want the mouseover and visited states then that's easy enough.

Code:
postbody > a:link {
  color: #0044BB; /* or whatever */
}

postbody > a:hover {
  color: #0044BB; /* or whatever */
}

postbody > a:visited {
  color: #0044BB; /* or whatever */
}

postbody > a:active {
  color: #0044BB; /* or whatever */
}
I don't see the problem. You change that to your colors and voiala! we can read it, and it only changes the stuff within the post body. Backup the stylesheet and try if you don't believe me. Just fix it and take it off the todo list, please, seeing as I've shown how it'll only take you a second to do.