Travel City have misinformed you about public transport, that being said, I have no idea where Highlands Reserve is!
We went for the 1st time in March 1999 without a car. We were staying at the Howard Johnson Hawaiian Court at the south end of I-Drive. We used taxis for a few trips to WDW, at $25 each way.
We found that the public bus company, Lynx, have a stop opposite Bennigans 800yds further south on I-Drive, at the intersection to (can't remember the road nr, but it's the one that comes from MCO). The bus runs hourly from Orlando to WDW, at $1 a fare.
There is a link somewhere on this board for timetables/routes for Lynx buses, perhaps one of the mods could help you here.