Researching high idle

I bought an ALDL cable ( http://www.aldlcable.com/sc/details.asp?item=aldlobd1u ) and it came with WinALDL software ( http://winaldl.joby.se/ ) and it's working fine. I just don't know exactly what I'm looking at. I see a bunch of numbers, but not sure if the numbers are bad or good.
The problem that I'm trying to track down in my car is a high idle problem. When the car starts, it purrs at 1k rpms, then about 30 secs later, it creeps up to about 1400 rpms and stays there. There must be a sensor or something wrong but I do not know what I'm looking at.
Other thing that was intereseting, is when I plug the cable into the car, the rpms go up to 1800. Yeah, weird I know (well for me it's weird at least, someone may know why).
I have reviewed the software's website and tried e-mailing them, but I haven't had a response yet.
Anyone have ideas or any other software I can use that works with an 84?
Thanks



