We are a couple in ours early 60's, reasonably fit, have not been to Prague or this area before, not into spending hours going from museum to museum but are willing to have a quick look at almost anything (did Louvre in Paris in under 3 hrs)
Would like to have a top 10 list before we get there and can add other items to the list as we find them. Also feedback on top 5 restaurants, we are staying at Hilton Old Town.
We will be there end of July before a river cruise
Always appreciate the feed back we get off Fodor

Prague is first and foremost a great, fairly compact walking town. It's fun to stroll. You can walk from the Old Town across the Charles Bridge to the quaint Mala Strana neighborhood all the way up to the castle at the top of the steep hill (plus great views from up there).

Just a warning: the stretch from the Charles Bridge to the Old Town Square is going to be mobbed with people during the day - it feels like navigating Disneyland with so many people. It can be uncomfortable. I'd walk across the Charles Bridge in the morning or at night to try to avoid crowds. There are other bridges to cross instead that are less crowded.

There are a few day trips you could easily make by train if you want - such as as a day trip out to the town of Kutna Hora where there are some interesting churches, most notably the Sedlec Ossuary (bone church), which is a tiny church full of human bones used to make little statues and chandeliers. (Google for pictures - may not be your thing.) I visited with a car but I'm told it's easy to do by train.

There are lots of Prague trip reports here. I'd search the Europe forum for Czech Republic postings and trip reports.

My number one for Prague is the Jewish area - and especially the old cemetery and the Pinkas Synagogue. The ticket is expensive - but in my opinion worth it.

http://www.prague.net/itineraries-in-prague
this is a good website for info on what to see and do.
July will be busy but try and get out early to see the most popular sites before the tourist hoards decend on them.
I can't really recommend resturants as I tend to eat well away from the city center but in the area you are staying there really is numerous places to eat within a 5 minute walk.

The highlight of our stay in Prague was a tour of the Jewish quarter with Wittman tours. It was exceptionally well done. Our guide was a doctoral student in Jewish history and provided an experience that was both informative and moving.

I suggest you take the tram up to the Castle, tour inside if you like and then walk down the hill browsing as you go. The is a small toy museum we happened on by chance and it was fascinating.

A little info inyourpocket.com/Czech_republic/prague

Another travel publisher, D------ K---------, has a series of Top 10 books for various major cities. It may have one for Prague.

I never tired of the Astronomical Clock and the Charles Bridge.
Very basic I know, but sometimes popular sites are popular because they
are very wonderful.

Mucha Slav Epic.

Wow!

A little outside of the main tourist area but not too far a bus ride.

In addition to what has been mentioned, we enjoyed the Mucha Museum in Prague. On our last visit to Prague, we toured the beautiful Municipal House and then had a late lunch/early dinner at the cafe in the Municipal House. There are several restaurants within the Municipal House.

OMG, mendota98, has the Mucha Slav Epic finally really be moved to Prague? We went all the way to Cesky Moravsky or something like that to see it--a bit off the beaten track, like several hundred miles. It is utterly fantastic and deserves to be seen by many people--as it will be in Prague but having seen it in the Czech "hinterlands" I'm a bit sad that that small town lost its only major tourist draw.

If it finally is in Prague (longstanding debate and feud about all of this), it most certainly would be one of the top 10 sights of that or any city. It is magnificent.

Thanks for the tips, have summarised points on to my travel notes

I have been to Prague twice so far. What tops my list is:
Prague Castle: Take the #22 tram to the top of the hill. You can spend as much time as you want inside, then walk down and stop for a glass of wine on the way down. The vineyard has been there since about 990 AD. There is also a restaurant inside the castle walls close to St. Vitus which was very good.

St. Vitus: I am not that much into cathedrals, but St. Vitus will take your breath away.

Old Town Square: I never tire of watching the clock ring in the hour. You can also go up inside the clock now (it had been closed the last time I was there). The square is a great place to people watch and stop for a beer or coffee.

Kampa Island is a nice stroll. There is a boat excursion that takes you through the "Venice of Prague"

Charles Bridge either at sunup or sunset is beautiful. We went during the day and while it was crowded, we did purchase some great photographs and drawings.

Petrin Tower. I enjoyed the view and taking the funicular to the top of the hill. There isn't an elevator so it's a hike up the tower.

Vyšehrad Castle. Just outside of Prague. You can take the Metro train to get there. It is the original site of the Přemyslid dynasty. We walked the grounds, had lunch there and visited the church grounds where there are many famous people buried (Mucha, Antonin Dvorak, and Czech composer Bedřich Smetana).

Have some great Czech food anywhere away from the tourist areas. Even 5 minutes will get you better food. We did eat at a place in Mala Strana which was very good; Kolkovna Olympia
Vítězná 7 110 00 Praha 1
+420 251 511 080
kolkovna.cz

Also the Hunger Wall Residence, where we stayed is around the corner. They have a nice cafe and great latte.

Mucha Museum. I love his art and we had to visit the museum. It is close to Wenceslas Square. It took about 3/4 hour to see it.