I dunno if above mentioned stuff would work. If you have bought second hand or smone gifted you then you might not have a valid Window CD.

I bought my previous Think Pad R 502 from ebay and had problems similar to you. I had two admin account and accidentally deleted them.

The easiest way for you is to hack your own computer. There are different websites which might help.

I used John the ripper. They had website which has this exe file which you need to burn in a disk and insert in your optical drive. Then after certain procedure it would give you some hexa-decimal code which you need to put in their website. You'll get your password (most of the time) in 48 hours. If you wanna pay some 30 bucks then you will get right away.

Try it. Thats how I got.

PS: For this, you need to get into guest account or sm other machine.

There are few in here. Try them.

http://pcsupport.about.com/od/toolsofthetrade/tp/passrecovery.htm