hi Shruti
I agree with Sabitha..

you told that you are planning in october..and i have spent oct here., its good (although day becomes shorter and no snowfall) but visiting swiss in winter is just like missing all the scenic beauty..as everything is covered by snow,, if you like snow then its okkk.. I think that swiss is best in march,april,july,aug and sep (as it becomes too hot in may and june and the temperature reaches 30 degree C,you will get sweat..!!) I have travelled lots of places in swiss but among them i would like to suggest you to must visit Interlaken, Basel, luzern, lugano and kandersteg.
you can visit to paris in Oct. As it doesn't take overnight journey from train, by TGV you can reach in 4-5 hrs from zurich..! (if you are planning to go by train)..but you should have atleast 4 days to visit paris.,as there are lots of places to sea. otherwise rome and vetican city would be perfect., It just takes 2 days.

..!! you can also visit to Munich, and can enjoy the world's most famous beer festival,octoberfeast from 19th sep - 4 oct

.
well..plan your trip,,enjoy.!
Love
LAZO