I've just finished reviewing Finale Print Music for technote magazine. This is an inexpensive scoring software, extremely easy to produce lead sheets by pc keyboard, midi keyboard or mouse, also with scanning input and microphone input for wind instruments. Also inputs and saves midi files, and converts encore and rhapsody files.
The website says XP is ok. For the money (around $60) I think its the best all round cheap program with the most options giving engraver quality scores.
There's a free download of a cut down version.