Hi Sauron
I'd recommend getting yourself an 030 accelerator board at the very least, along with some extra memory.
My particular favourite combination is an A1200, with Blizzard or Viper 030/50MHz and some decent RAM, say 32 or 64MB?
I'm also a big fan of the PCMCIA CD-ROMs you can get, like the Q-Drive etc.
I find the towered A1200s a bit too hacky for my liking, particularly if you are transporting to a User group or something like that, since something always seems to get dislodged and you spend half an hour trying to put it all back together again
Anyways, have fun - the A1200 is, in my opinion, the best Amiga ever made and you'll have some good times with it.
If you have a PC, then an easy way to d/l files would be to get yourself an Amiga CD-ROM drive and use Aminet and then burn files to CD and transfer them over - I do this using my AmigaOne (or did until about 3 months ago).
OS recommendation: OS3.5 or 3.9.
Rude!