That's very good !
You can get into BIOS , so you now "own" the machine .
CD as #1 boot option is just fine for now .
What you do next might depend on getting an internet connection , on a different machine .
If you can find someone who can download a file from the internet and put it on CD/DVD for you , there are these options
a] Download an Operating System of your choice .... Mint is ideal of course ( Microsoft will want your money , and more ! )
b] Download a " Utility Disc " and use it to repair GRUB .... Parted Magic is the easiest to use IMO , but there's Hirens , Ultimate Boot repair disc
And if none of that is possible there is still
c] GRUB Rescue
Note that Pjotr has recently updated with some very useful info , above ^^
Looking back on your posts I have to say that option [a] is probably your best bet for getting up and running , quickly and painlessly
And if making a disk is a really serious problem for you , some kind soul may offer to mail one to you , ready-to-use and free of charge ?
The other two options are going to need guts and determination , but they WILL work , eventually
Edit : everything I have said about disks will work just as well and faster using USB sticks , but you might need to change that boot order in BIOS