The bottom line is that the $9.95 a year domain registration fee is not refundable. You can buy a new domain and it will cost $9.95 for the first year of domain registration. In subsequent years, you can use your free domain registration to renew that new domain. You can just let the original domain you don't want anymore to lapse and expire.
I didn't quite understand this part of your post.
What are [color=#CC0000]50DISK50[/color], [color=#CC0000]3DOM50[/color], and [color=#CC0000]1IP1DOM50[/color]?
They're Dreamhost coupons!