§MrMobeus:
Well, where to start? Let´s try with: You´re a brave man.
First of all, no version of the Amiga OS is freeware. So you´ll have to grab a copy from a dealer near you (or from a dealer on the net). Mind the Kickstart version needed! Ubuntu? Better use the PC!
The A500 is rather limited when it comes to expandibility. It only has the trapdoor expansion-slot and the slot on the lefthand side of the machine. This last slot is used by a few external Harddisk controllers. The Amiga 500 does not have an onboard harddisk controller, so you´ll need an external one or get yourself a turbo-board for the A500 (which will go in the trapdoor expansion slot) with a SCSI or IDE controller. Then if you´re really brave (and handy) you might be able to hack the casing to shoe-horn in a harddisk.
Other solution could be hacking a big box PC case to accomodate the A500´s mainboard. In such a case you´d be able to also hook a CD-ROM player as well. But prepare for a lot of hacking sharp metal. And you´d still need a harddisk controller, eather on the edge-connector or on the trapdoor expansion.
So, yes you can use any of that hardware, but you´ll need extra hardware as well and you might have to crawl the net a lot to get pin-outs and hardware hacks to get everything done. And the additional hardware needed offcourse.
