Easy to reset it with out the recovery CD.
Press either F11,F10, F9 , or maybe F12 at your Boot Up Screen One of these should take you into the system recovery mode where it will give you the option to either recover from the Recovery CD or the System Recovery partition this will effectively wipe the password from the hard drive and reset it back to factory specs.
Then you should be free to set up your dual boot.
BUT I would make me a set of recovery cds/dvds of the factory image before doing the dual boot either through the windows recovery manager or dell's oem recovery cd/dvd maker.
I have no idea if once it's dual booted you'll be able to access the recovery partition or not, So that's where the Recovery Disc will come in handy.
You can also go to dell's support site and type in the Service Tag# or manually look and match up the model of the laptop and get your needed manual and or drivers you'll need there.
I have a dell inspiron M511 so I am kind of used to them as I've also had other dell's as well.
Is it password protect on just booting up the OS?
OR is it password protected on the bios boot up or worse yet the hard drive?
The second one is hard to get around but it can be done most times.
BUT the third one if it's a protected hard drive without the password the hard drive is useless and will have to be replaced.
I hope this helps?
And if I can help any further let me know and I'll be glad to help you if I can....
