Distro is distribution (or brand), RHEL, Centos, Fedora, Debian, Slackware, and tons of others. While they are all Linux, the details of how things are handled in each one is slightly different.
Arch is architecture it is built for, x86(32bit) and x86_64(64bit) are the most common. If you post the results of:
It will probably tell us a lot.