'97 sounds about right (give or take a year). http://www.bikepedia.com/quickbike/B...e#.UC1_XqCTJ1M

Seeing as it was probably around $430-$475 (MSRP) new, I'd say it's probably worth about $150 if it's in decent condition...but it all depends on location & condition.

If your current bike is one that was originally purchased at WalMart, Kmart, Target, etc...then, yes, the GT will certainly be an upgrade, and your current bike is probably not worth putting any money into.