2009 mbp wont bootup

Question

Greetings,
The other day i was hooking up my 2009 13' MBP (2.53ghz 4bg ram 320 jdd) to my hdtv via hdmi and i noticed the screen had frozen. Stayed the same upon opening and closing the lid so i tried to restart via the power button. The grey startup screen wpuld then comes up and stay considerably longer before the apple appears and the spinning grey ball  continues for up to an hour with no progress. Tried unsuccessfully booting into safe mode, reset the PRAM and NVRAM and now when i power on im met withe flashing question mark folder. I was able to hold option and select macintosh HD to enter single user mode. checked my hard drive volumes and was met with the prompt 'macintosh hd appears to be ok' which im told means its not hard drive failure. I presume that my next step would be a reinstall but i have a few questions.
1. I received my MBP brand new in '09 running snow leopard but received no disc. I am running the latest version of lion. How would i go about reinstalling in this specific instance given the lack of disc and current version?
2. I've never attempted anything like this before and although i've read a few places that a reinstall over the current version will leave my data archived under 'previous system', a bit of reassurance would go a long way before attempting this. I've got a photo loving wife who has made the mistake of not backing up a few years worth of memories and.......... well you know the rest.
3. Maybe i've not considered other options?
Thanks for reading and I appreciate any and all help.

Answer 1

All you need to do is the following and nothing else to reinstall Lion:
Reinstalling Lion/Mountain Lion Without Erasing the Drive
Boot to the Recovery HD: Restart the computer and after the chime press and hold down the COMMAND and R keys until the menu screen appears. Alternatively, restart the computer and after the chime press and hold down the OPTION key until the boot manager screen appears. Select the Recovery HD and click on the downward pointing arrow button.
Repair the Hard Drive and Permissions: Upon startup select Disk Utility from the main menu. Repair the Hard Drive and Permissions as follows.
When the recovery menu appears select Disk Utility. After DU loads select your hard drive entry (mfgr.'s ID and drive size) from the the left side list.  In the DU status area you will see an entry for the S.M.A.R.T. status of the hard drive.  If it does not say "Verified" then the hard drive is failing or failed. (SMART status is not reported on external Firewire or USB drives.) If the drive is "Verified" then select your OS X volume from the list on the left (sub-entry below the drive entry,) click on the First Aid tab, then click on the Repair Disk button. If DU reports any errors that have been fixed, then re-run Repair Disk until no errors are reported. If no errors are reported click on the Repair Permissions button. Wait until the operation completes, then quit DU and return to the main menu.
Reinstall Lion/Mountain Lion: Select Reinstall Lion/Mountain Lion and click on the Continue button.
Note: You will need an active Internet connection. I suggest using Ethernet if possible because it is three times faster than wireless.
EDIT: Your computer should have come with a set of two DVDs. You can contact Apple about purchasing replacements:
Apple Store Customer Service at 1-800-676-2775 or visit online Help for more information.
To contact product and tech support visit online support site.
For Mac App Store: Mac App Store Customer Service.
For iTunes: Apple Support for iTunes - Contact Us