As I said - 50 to 80 adapter would be quite cumbersome to mount and it would require some hassle with proper bus termination. Get ATTO SE IV and you can easily connect any modern, 68-pin LVD drive + LVD cable for cheap. As a bonus you'll get about 2x performance of builtin SCSI.
To write Mac disks on the PC you can try this method:
http://macfaq.org/software/macos.shtml#Q1.1.6
And Quadra 610 should have AAUI ethernet port - all you need to connect it to your home networ is proper (and again cheap) adapter - probably the one for twisted pair cable. They are popular and easy to spot on eBay.
Word 5.1a or Wordperfect 3.5 (freee) - both nice and very competent word processors. If you get an AAUI adapter, then exchanging data with PCs shouldn't be a problem.