Which Eurail Pass should I choose?
Which Pass you should choose depends first and foremost on where you want to go. If you're planning to visit a single country, you can choose the One Country Pass for that country. If you want to visit multiple countries, the Global Pass (valid in 31 European countries) is your best bet.
Secondly, you should choose a Pass that matches the number of days you plan to use the European train network. These so-called travel days are offered in a wide range, starting at just 3 days and up to a maximum of 3 months.
Finally, if you're looking for a little more comfort and luxury, a 1st class Pass is the way to go. If you're watching your budget or don't care much for luxury, 2nd class is the more affordable option to see all of the places on your list.