Recovering files after reinstalling windows 7. Urgent help needed!!!

hello everyone
i have a windows 7 ultimate 64 bit on Lenovo B560 laptop.
yesterday i downloaded bluetooth driver from the lenovo site, when the already installed driver was not working and also not getting updated.
when i was installing the driver, after some time it seemed as if the system has hanged. so i ended the process through start task manager, thinking to reinstall it. as soon i ended it, i saw many of the files on my system were missing.
i tried using system restore, but of no help. from that time on i got the message:

Boot Manager:
Windows failed to start. A recent hardware of software change might be the cause. To fix the problem:

1.Insert your Windows installation disc and restart the computer.
2.Choose your language settings, and then click "Next".
3.Click "Repair your computer."

If you do not have this disc, contact your system administrator or computer manufacturer for assistance.

Status: 0xc000000f

Info: The boot selection failed because a required device is inaccessible.

i tried everything possible to repair, but ultimately i had to reinstall windows.
now my major problem is all the data and softwares on my system are gone and i have no idea how to recover it. i do not have any system image or as such any backups. i handled any blunders in the past through system restore but that is not working.

i am a novice at using computers and do not have much technical knowledge.
pls someone help me!! i have my project to submit.

thanx in advance.

Did you have multiple partitions on your hard drive when you reinstalling win 7?
If you go into disk management you can easly determine this.

hello Josea and Kaktussoft
firstly, thanx for replying

before reinstalling windows, my hd had c: and d: partitions; c: had windows installed and most of the data, s/w. d: had some data.
before reinstalling windows i tried system recovery from installation disk. there i also looked in the option of loading drivers. then i noticed in 'open driver' window that my c: drive became d: and d: to e:
i could make this out by looking at the space occupied by drives.
at the time of reinstalling it was mentioned that the old data will be copied in windows.old folder.
after reinstalling also i have c: and d: drives. data on d is there. but windows.old contain mostly empty folders or system folders. all my documents, data and personal data all are gone.

when i got Status: 0xc000000f error i tried every option that showed up for recovery, but it got me back to the message:

Boot Manager:
Windows failed to start. A recent hardware of software change might be the cause. To fix the problem:

1.Insert your Windows installation disc and restart the computer.
2.Choose your language settings, and then click "Next".
3.Click "Repair your computer."

If you do not have this disc, contact your system administrator or computer manufacturer for assistance.

Status: 0xc000000f

Info: The boot selection failed because a required device is inaccessible.

yes i do have c:\windows.old\my username folder. it contains many of the older folders(not all) but furthermore most of these folders are empty.

hey Jim, thanx for the suggestion :)