Tokyo, Yokohama or Osaka?

So me and a couple of friends are planning a trip to japan pretty soon but between us we can't decide which, out of the 3 above, would be best. None of us have been to japan before so which city is sorta the friendliest or most interesting?

Tokyo is by far the most interesting of the three cities and also offers many interesting side trips (one of which is Yokohama).

Osaka is also a very interesting city and offers even more interesting, easy side trip options.

About Tokyo and surrounding:
http://www.japan-guide.com/e/2164.html

About Osaka and surrounding:
http://www.japan-guide.com/list/e1105.html

the Osaka region is called by many Japanese the birthplace of Japanese culture and civilization. Osaka is much smaller than Tokyo but has lots of great department stores, modern buildings, older areas AND Osakans are famous for their love of good food. Nara was a capital and has lots of temples and shrines. Kyoto was Japan's capital for1000 years and has over 1600 temples ,shrines, gardens and a few palaces. They there is Kobe and its old European district , a Chinatown, a mountain with cable cars and old onsens. There is also the amazing castle of Himeji and its garden. let's not forget about Koyasan mountain and hundreds of temples... and there is more, way more!!! All the towns noted above are close to one another by frequent trains. .

I recommend Tokyo when you compare Tokyo alone with Osaka alone.
This is not because Tokyo is more attractive than Osaka, this is because it is easier(and more expensive) to get around Tokyo than Osaka, due to the amount of usable English information.

If you have more than 3 days and plan to do some sidetrips, I definitely recommend Kansai(Greater Osaka) than Kanto(Greater Tokyo).
http://www.japan-guide.com/list/e1105.html