20 yr old science classes, too old?

I have a feeling I know the answer and I am already leaning toward retaking all science classes just so I will have a better understanding, but what do the adcoms consider recent? I’m thinking 20 years really doesn’t count. If that’s the case I need to get crackin’ to make the fall 2009 application timeline.

If I go full time would anyone recommend taking 3 science classes at once?

What about the english classes? Do I have to retake those also?

How about online courses thru a university if I can find one local that I could do lecture online and in class lab? Any ideas on that?

Thanks for your help!