I have a rigid Rockhopper right around that year with the STX (although it is steel). My $.02 is keep it rigid and perhaps SS as psychlnut suggests (although we don't all live in Sarasota...).

By the time you switch out the headset, races, stem, spacers, fork, you're sinking a good bit into what could be a significant future investment. And risking the geometry being really sloppy.

Ride the hell out of the RH as is and save your pennies for the next bike. Then commit it to commuter duty with slicks fenders and a nice rack.

I continue to believe that most of us can really enjoy a rigid ride on varied terrain (unless you are planning on riding mostly rockgardens and big drops). YMMV.