So I understand the http://us.blizzard.com/support/hackswebform-us.xml but I would like to know what would would need to be included as proof and documentation to ban users for using mods.

Also, is there any way to see how old my account is?

Thanks!

Hyperlite_:-) ,

When using that form, include a summary of why you believe the person is hacking and what they are doing. No actual proof needs to be submitted with the report because we always do our own investigation.

There aren't any commands to see the age of your account. But you can find a listing of all chat commands here:
http://classic.battle.net/info/commands.shtml