Cross country MTB's make a great trailer tug. For a baby seat it helps if it's a stepthrough, but you can't really find stepthroughs as good as your bike. The bike is a good one! It cost $900 according to the Internet, that's $1300 today. You can take it to a bike shop for a checkout if you are nervous. They will probably want to rebuild the bearings, replace the cables, and sell you new tires. You can still get compatible components, with the possible exception of the fork. There are places that will service your fork, if you think it deserves it. It was a good one for its time. But suspension has come a long way... and you can also find a good modern fork for a good price, new or used, the bike shop might be able to help. The elastomer forks went obsolete and got replaced by coil springs and oil damping, and later air springs. More expensive ones are lighter with more adjustments. Or, if you don't intend to go off-road much any more, you could replace it with a rigid fork for much cheaper.

If you are interested in something new, the newest crop of mountain bikes have 1x10 or 1x11 drivetrains, bigger diameter rims, sometimes bigger 3" tires, more leaned-back geometry with a shorter stem and wider handlebars. I want one but my poor old Hardrock keeps persisting.