It really depends on which course you're going to be doing - Melbourne and Monash are both some of the most prestigious Universities in Australia, and quite likely the world depending on what your area of study is.
If you go for Melbourne Uni you're looking most likely at the city-based campus (there are a few other satellite locations but most students never see them) and a lot of history as it's the first Uni Victoria got. Keep in mind that affordable accomodation near the university is relatively difficult to get, although it's not too hard to live further out and commute in as the public transport there is pretty good. It's a good name dropper, you may well meet the future movers and shakers of Australia but I've heard some of their courses can be a little dry and short on practical knowledge.
If you go for Monash Uni you're most likely looking at the Clayton campus which is a half hour DRIVE from the city. Unless you live close to the campus and a train station you will find it hard to get around socially without a car. There are other campuses - Caulfield is a little better connected to public transport, Peninsula is practically car dependant. Monash still is a prestigious uni though, and in your industry may be better thought of than Melbourne Uni. And accommodation will be cheaper as its further out of the city. For the record - I went to Monash Uni (caulfield). The course I wanted to do wasn't offered at Melbourne, but my brother went there.
ANU I don't know much about - I've heard of some people going there, especially because they really liked the look of the course. So maybe if their course outline looks really good, you should consider them anyway. But certainly it's not as well known and I'm not sure of its reputation.
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