This isn't a total solution, but it might set you on the right track. It seems that Terminal.app will take any arguments that you pass it, and execute them as UNIX commands. For instance:
open -a /Applications/Utilities/Terminal.app /usr/bin/top
will tell Terminal.app to open the program /usr/bin/top. A new little window will pop open, and top will be running inside. Quit top, and it will say Process Completed. You can also get the same results by dragging the program onto the Terminal's icon in the Dock. The only thing I haven't figured out is how to specify the window size at launch. Knowing that this works, you should only need to find a way to script it.
I was actually trying to figure this out myself, once, but since I'm no AppleScript expert, I was having trouble telling Terminal.app to open a particular file. Let me know if you come up with anything.
It's been quite a while since I've scripted. I tried for a little while to open a file with a particular application and quit with frustration. It Seems some AppleScipt events are handled a bit differently in OS X. I might give this a second try once 10.1 comes. I heard more apps are scriptable like Terminal.
I'll correct myself in the previous post. The saved Terminal file is not an executable but just a plain file. It just happens to have the file extension .term which when double clicked will open Terminal and then the executable it was saved from.
If you open this .term file in a text editor you will notice it appears to be in xml format listing the key and strings for Terminal's property list. If you scroll down a bit, notice the string for the key "Shell" is the path for the shell script in which this key references. So if you change location of your shell script you would need to change this string to reflect the change. Basically this file will open your shell script with the properties of the Terminal window you saved.
I experimented with changing text color by altering the string for the "Color" key. Can change the window title with the string from the "CustomTitile" key. I guess you can go to town with customizing this if you so please.
I also tried to accomplish what you would like to do with AppleScript but with shell commands (open a file with a particular app). I guess the object is to get a double clickable file to do what you want it to do. ex. open somefile.txt with TextEdit.
In this example I wrote out a shell script (which I'm fumbling over myself) like this;
/usr/bin/open -a /Applications/TextEdit.app somefile.txt
Saved it with the .command extension, and made it an executable. This would be your double clickable file.
Another double clickable file example that would open top in a shell with saved window parameters would be this;
The shell script:
Saved it with the .command extension,and made it an executable. Ran it. Adjusted the desired window size and saved it from Terminal with the "Main Window" option. Buff, your double clickable file.