It depends! When you say replace, what type of flooring do you have now? What type of floor do you plan on installing?
If you are planning to install ceramic tile where lino used to be, you may have to use a different subfloor you should look at the support under the floor to make sure it can handle the weight.
(I think the weight of ceramic tile per square foot is 7.62...ONLY KIDDING, read some past post.)
Seriously, if you are installing lino, you would be wise to put down a thin subfloor first after you take up the old stuff. The reason for this is because the new lino will show every flaw and spec of dirt.
If you are planning to install hard wood it will require different prep work.
Removing cabinet base units will depend on your preference, time, and money. If you have the time and the money and you believe you will be able to remove and re install the cabinets and counter tops, and handle the plumbing and any electrical involved, I would work with an empty room.