Rome pretty much sucks on a lot of fronts if you're thinking it's going to be rustic and "Roman". I spent a week there in 2007 and the beer scene was so-so, so I stuck to really good Italian wines. If you're looking for beer though you can check out the Bir & Fud Pizzeria:
http://birefud.blogspot.com/2007/09/bir-fud-la-pizzeria.html. Lots of local stuff and imported stuff (you'll pay for it), but great pizza as well. Not that you want American beer while there, but from their site the American beers they have are Great Divide. Left Hand Porter. Flying Dog. Samuel Adams. Anchor. Sierra Nevada. Rogue. Jolly Pumpkins. Of course you'll be looking to drink all of the Panil you can
EVERYTHING in that city is touristy. Hell, even the Pantheon is a stones throw from a few fast food joints and gelato stands. The public transpo is ok, but it's incredibly sketchy. The Rome metro is two lines that form an X and it will get you about everywhere you need to go, but like TT said walking the city is the way to go (except at night). The commuter lines will take you all the way out to the coast if you want them to. I didn't bother with buses there. Check out the Palatium wine bar in Rome, as it's pretty much the go to spot for Lazio (the wine region of Rome) wines, and the food isn't bad.
I cannot stress this enough: GO TO FLORENCE. The city is abso####inglutely beautiful, the surroundings are beautiful, and the food is incredible. It's a smaller city, architecturally amazing, and really easy to navigate. From there you can also take a quick day trip out to Pisa. I would live in Florence for life if I could.
Edit: Just looked at Brasserie 4:20's page... looks like they have a pretty cool selection on tap and in bottles, but the bottle prices of those "Vintage Lambik" beers are crazy!
