Most you can do with a lawn tractor is maybe run a dethatcher , small roller,and just a bit better for plowing snow , than shoveling it .
A garden tractor can have many more uses such as plowing garden, pushing dirt , gravel,will possibly use a tiller (Depending on the gearing)So many more uses than a Lawn tractor.
The SS 16 ? you can still find many implements for. even a sickle bar mower Heavy gearing with real bearings vs. light aluminum cases for rear end with bushing style bearings.
Don't feel you ask a dumb question. Many folks feel they have a garden tractor for sale when in fact they just have a lawn mower.