Prague to Vienna

Train.

Hi Margo,
... when you step off the train in Vienna, there will very likely be no baggage trollys handy. Easy solution:- have your partner sit on the bench watching over your bags while you walk into the station where a trolly is waiting for you to take. Then, go back and pick up your bags. [Don't forget your partner]. The trolly probably has a handle which puts on the brakes when you release it. So, to be able to push the machine, squeeze on the handle.
In the station, you can buy 72 Hour Vienna tickets for nearly all public transit in Vienna... you validate it by placing the end of your ticket into an appliance on the transit car called 'ENTWERTER'. It marks the beginning time of your 72 hours ticket.
... Gute Reise! Vienna is a wonderful place! P

Booked through Austrian Rail, SparSchiene fares can be as low as 19€. See here: www.oebb.at/en/index.jsp. While you can book online, everything reverts to German when you get into the booking process. The easiest way to book is by phoning the Call Center. Dial 011 (US international access code) + 43 (country code for Austria) + (0)5-1717. Omit the zero in parentheses. It is only used for calls originating in Austria.

Like Tim mentioned:
TRAIN!
A pleasant four hour trip, cheap to boot if you book it right.
Make sure to take the train that takes only 4 hours, and arrives at Wien Südbahnhof - or you might travers Bohemia the loooong way, speak 8 hrs +!

let me know if you need more info, I'll be glad to help with details.

Margo,
... You are very fortunate to have access to someone like Corinna to guide you. Be sure to accept her offer. All the best, P