If you are looking for a version of the dt that provides graphic files for printing try Yet Another Digital Tradition. The site seems to be down at the moment BTW.

The Mudcat online version does not provide that but it does provide MIDI sound files which can be used to produce printed music provided you have suitable software (something I thoroughly reccomend getting). Noteworthy Composer is a reasonably priced shareware program that seems to be popular amongst users here that provides printing and editing capabilites.

If by "Irish and Scottish" you were looking for Jigs, reels, etc. rather than tunes to songs, pay a visit to John Chambers Tune Finder it is a superb resource.

Jon