Dear Rahul,
JMS can do almost everything that you one except having a unique administration of all the webiste.
With JMS, you can create a small website without any content but with pre-installed blog, forum, photo galleries components, ....
Once you have defined the "fresh" website that will be used by your customers, you can define in JMS a "Website Template" rule that will use this "fresh" website as the one that will be replicated for your customers.
This will give to your customer a new website that will be the replication of the one that you will have created as template.
JMS gives the possibility to offer the website creation from the front-end.
This means that you could propose this service to your customer and up to you to propose them one or several "website template" ready to use.
JMS does not share the content between the websites.
This mean that the articles, forum, new, USERS, .... will be totally independent.
As the users are specific to each website, this means that if you want to also administrate the websites, you will have to login on each individual websites.
I suggest you have a look to the video present in the tutorial.
See the Step 0 that present the concept
and the step 13 that present the case of a websites creation from the front-end.
www.jms2win.com/tutorial