The original F does stay on the transcript but you can always retake the class for a better grade. Its the second grade that counts towards your overall GPA not the original F. As long as you've just failed one class rather than several, I don't think this aspect of it should be too worrisome.
The worst part of getting an F is that it can seriously set you back both financially and timewise. College courses are expensive and if you have to retake a course, that's alot of money. Even if you don't need to retake the course, if you got an F, chances are you didn't get much out of the course, so its still money wasted. If you have to retake a course that's required for your major, it can end up delaying your graduation, especially if that course is needed to take subsequent ones that are also required.
5w6 or 9w1 sp/so/sx, I think
I ended up taking the class again during "normal school" hours and took the next class in order over the summer. It kept me up with the rest of the graduating class. The prof that failed me became one of my favorite profs. I did learn from the experience since mine was just pure laziness so getting the F woke me up.