I think this display might be on the way out. It's a cheap Acer about four years old. Noticed some moire type patterns when I hit sites that used blended backgrounds yesterday, but of course not today.
Hope it helps. With the number of LCD displays out there (even in Vista and Win7) Cleartype is NOT a default, nor is offered during setup of machines. It DOES make a difference in text display. Can't tell you how many times I look like a magician to clients when I "make" their text readable. :)