I have a big bad problem!

I buyed second-hand latitude d 630  without any documents.

fev days ago i got windows crashed cuz of 86 viruses in system

I used dr.web Cure It and he asked me to restart windows to finish fixing problems

but after restart i got the massage that windows cant load and it started searching and fixing problems automaticly but it didnt helped.

In some ways i formatted C and D sectors of HDD and wanted to reinstall clear windows os but iv got msg thet some files cant be copied  from dvd room to c/windows~(something like that), (HDD already formatted)

Then i decided  try it later and shooted down laptop.....omg...

NOW there is  Unlock setup and admin password setttttt in bios and i cant run windows install from dvd disk

The reason that i used dr.web previosly is i couldnot reinstall clear windows from bios cuz of passwords.

Now i cant do nothing with it:when i press laptop power button im just seen the msg:

BOOTMGR is missing   press ctrl+alt+del to restart

KRD2015611

Custumer PO: 07U352B2BDKRAFT

Model: D630

Service tag: <ADMIN NOTE: Service tag removed per privacy policy>

express code : <ADMIN NOTE: Express service code removed per privacy policy>

PLS DELL help me with it!how to reset those passwords? im from Ukraine i cant call tech support cuz  its costs money!(