Well there programs out there that can sometimes salvage the data off old disks. Of course if they are games, most Amiga games have been released as Freeware if not abandonware, so those are mostly all available from the net now a days.
If you want to take the shift from the 1200's kick ass Keyboard set up, to a tower, then you might as well make it worth you while and get this when it comes out:
http://www.elbox.com/news_04_12_17.htmlAnd when OS 4.0 non-beta is out, Elbox plans to release this:
http://www.elbox.com/dragon_photos.htmlOf course you have to be filthy rich, or a good saver, if not gifted on Ebay.

In the end, I think you will be happy with what you got. Just compare the prices of this set up to a rare 1200 060 50MMhz, plus a Mediator Bus Board. You'll still be spending about the same, and only have a fraction of the features.
As for tower, you can build your own (I'm working on finding blue prints for this as we speak.), or you can buy one like this, which I assume comes with a PC Keyboard and Mouse adaptor?
http://www.elbox.com/products/d-box_1200.html Anyhow, I'm in the same place you are, been away, and am now coming back, starting with a trusty 1200. Looking to upgrade, re-learn the world.
You should of titled this:
Computing: From simple, to complex.