Our MacDisk is a program to read/write/format physical Macintosh media on a plain PC.
It answers a broad class of needs, but cannot satisfy all, of course.
Amongst other solutions to consider are hybrid networks and emulation solutions.
We give below some links to help you to explore those solutions.

Hybrid (Mac/PC) Networks
Instead of trying to reinvent the wheel, we chose to redirect you to the superb MacWindows Site.
In particular, it offers a very good page on Cross-Platform Networking Solutions.

Emulating a Macintosh on a PC
Once again, we recommend you visit the superb site of John Rizzo. It proposes a page on Mac emulators and another on Emulators to run Mac software.
Don't ask me why there are two pages on this subject, I don't know ;-).

Apple UK on Mac-PC Relationships
Apple UK publishes a very good page on Mac-PC relationships, even if our solutions are ignored.