The public transport system is quite good and cheap.

I found that it wasn’t all that easy to communicate with people in English, learn a few phrases in Hungarian if you can. However, I was there in the wintertime.

There is plenty to fill up seven days.

A day trip: go see the statues. There’s a statue park that contains the monuments from the Soviet era, it’s outside of the city because there are still very strong feelings about this era and they don’t want the statues vandalised. Well worth a visit, make sure you invest in a CD entitled The Best of Communism – now that I just couldn’t pass up! You can get a bus to this place.

Invest in a DK Eyewitness Guide for Budapest and make life easy for yourself.
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I’d recommend going during the spring or the fall, to hopefully avoid the largest crowds of tourists, but when the weather is still favorable. I don’t know anything about the nightlife because I almost never wasted time in bars or clubs anyplace I went in Europe (one bar or club is pretty much the same as any other no matter where you go). I didn’t say in a hostel in Budapest, since I was staying in one in Bratislava at the time, but I know the city has plenty of them. Hostels.com or Hostelz.com can probably recommend quite a few good ones. You can meet young people anywhere; the city is pretty youthful. Many Hungarians speak English (if that’s your native language), especially in the capital. I didn’t use the public transportation system because I walked all over the city. Yes, there are plenty of attractions–I only got to see most of the more well-known places in the city, and even then discovered I missed more after I left and did a little more research into Budapest. You can probably find enough to do to fill up seven days, although I would recommend at least visiting some of the other cities and sights in the country during that time, and maybe some of the neighboring countries (Romania, Ukraine, Slovakia, Slovenia, etc.)

If you like sightseeing, photography, shopping, people-watching, and doing the backpacker thing, Budapest will come quite naturally to you. There are plenty of villages to visit in Hungary and its neighboring countries if you need a change from the urban lifestyle, and as for football… well, I know next to nothing about sports, but I know that Hungarians, like most Europeans, love that sport. I’m sure there’s a game or two to be found if you time your visit right.
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Visited Budapest a little over a year ago.