I like tall windows; there is no reason to limit windows to 24 rows. Make your default window almost as tall as your screen. Then open another one. Terminal starts the new one slightly down from the first one, with the bottom of the window running off the bottom of the screen. D'oh!
Solution: create about five windows all the size and shape and location you want. In the Shell->Save As command, give this set of terminal windows a name (like "five good windows.term"), set "What to Save" as "All Windows", and select the "Open this file when terminal starts up" option. Quit Terminal, and when you start Terminal each time, you'll get your preferred set of terminal windows.
Oh, and don't forget fonts. The wrong font can make you go blind. My preference (for a PowerBook screen) is Andale Mono 11 pt. It seems to have the right balance of size and inter-line spacing. I'd be interested to hear if anyone else has a strong preference for something else.