I have just returned from 3 nights in Rome staying at the Hotel Marc Aurelio. I feel that other reviews posted on this site do not do the hotel justice, or maybe the hotel has improved greatly since they were written.
To be fair, the hotel is not in the centre of Rome. It is about a 20 minute journey, between walking and the metro, to get to the town centre. However, the hotel sits about 5-10 minutes walk from the closest metro station - Cornelia - and is 5 stops from the centre of the city. The service on the metro is reliable and fast and we didnt get pick-pocketed at all (although I hear it is quite common). The hotel is on metro line A which stops at the Vatican, Spanish steps, Trevi fountain and Pantheon, with most other attractions - Colosseum etc, within a comfortable walking distance. In general, it is pretty easy to get to all the attractions of Rome as long as you have a map (a good tourist map is provided by the hotel on check-in) and are wearing comfortable shoes! (A mistake I made on the first day!)
The staff are friendly and speak very good English. They were more than happy to help whenever we had questions, and whilst the breakfast was simple and could have been fresher, it was definitely edible and provided much needed fuel for a long days sightseeing!!!
The room itself was clean and spacious enough, with a reasonable mini-bar and ok views, and there were always clean towels and hot water (in contrary to what other travellers have written on this site!!) In our experience, the air conditioning was definitely not too noisy and very efficient!! The bathroom was equipped with both a shower and bath as well as a bidet which we definitely werent expecting!
One thing that was a bit annoying was that the metro stops at 10pm most nights, but bus number 46 stops at the end of the road, as does night bus number 5 (depending on what time you decide to go home!!!) You can buy a 3 day metrebus (metro/bus) ticket for 11euros and then enjoy exploring the wonders of this gorgeous city!!!
In general, I think that the hotel has been a bit under sold on this site and that really it was better than we had expected. The fact that it is a little way from town shouldn't put you off staying here, as long as you are able to walk a bit and have a bit of sense of adventure, its a pretty cool hotel. And much better than anything you could find in the centre of Rome for the same money!!!
P.S. its not on any of the '10 must-visit places' but I would recommend that you go to the church San Marco, near the Monumento a Vittorio Emmanuelle, because it was beautiful and quiet and really cool inside and there weren't crowds of tourists destroying the atmosphere!!!
Enjoy your holiday!