Old thread but let me reiterate that Spare Parts does not change font size anywhere but inside the app, which just means you can read the other settings options better. Useless is right.
Android, or should I say I, need font size adjustment in Email, Contacts, Calendar. I just can't read them comfortably. It's now a year later and the latest Gingerbread OS doesn't offer it either.
After trying out an Optimus S running Android 2.2.1 I'll be returning it and sticking to my BB for primarily this reason. The BB's system wide font size adjustment beats hell out of Android for anyone over 40. iPhone too.
The white text on black in the contacts is for kids too I guess. While email uses it for the subject and preview lines, at least when you open one it goes to black text on a white background.
Contacts stay in Darth Vader mode even when you open one. I couldn't believe it when I discovered the little document icon beside your notes in a contact. Press and hold it and your notes revert to black on white text, so you can read them! Lamest thing on Android imho.