Assuming your month is 30 days, you have ten destinations, so that's only three days a city - NOT counting travel time, which will be half a day or so most times you move. So I think you need to cut a good bit of your list. Personally I'd give London, Paris, and Rome all at least four days each (and you could do more).

Whether to buy a Eurail pass will depend on your final itinerary. Once you figure it out, you'll need to price the pass vs. point-to-point rail tickets and/or flights between each spot. These sites will be helpful.

http://www.bahn.de/i/view/USA/en/index.shtml (train schedules)
whichbudget.com (flights)

Keep in mind that if you use budget airlines like Easyjet or Ryanair, you'll need to pay close attention to extra fees and baggage weight limits.

Thanks for the links @ Jent103.

HOw about London, paris, Madrid, Belgium, Germany, Rome and Athens.

Hello!
I think you should think of specific areas rather than whole countries. What means Germany and Belgium? Do you have a specific destination on mind? What attracts you on your chosed destinations at first place? Sharing a bit about your interests etc would help to narrow it down a bit...

I agree with mariha - saying you want to visit "Germany" is like saying you want to visit the West Coast. It's a big area. Are you planning to stick with just Berlin, as in your original post? Or are there other areas that interest you (and why)?

In terms of time this itinerary is more doable (assuming you just mean Berlin), but you're going to a lot of cities that are far apart. So you'll have to plan on more time for just getting to places, and you'll be looking at several flights (mainly to Athens, Madrid and Rome, but depending on your itinerary, maybe another one).

Since your still figuring out your itineary, I would encourage you to consider squeezing one or two non-city destinations between some of the major cities. After a while, big cities all start to feel the same. Taking a visit to the mountains, countryside, or beach will feel like a vacation within your vacation, and may well provide the most memorable experiences of your trip. Happy planning!

To be honest, i have only picked the countries for now. I was thinking that I will start looking at attractions in each place and work out the stay.Coming from australia, I have very little knowledge on the places I would want to visit.
I have picked them from different forums and settled on the 7 places.
I like the idea of visiting the countryside.
The fact that I arrive at Frankfurt and depart from London, i sort of want to take a round trip visiting the basic countries.
I am happy with suggestions.

"Coming from australia, I have very little knowledge on the places I would want to visit."

I hear they do sell guidebooks in OZ . . .