Thanks to all of you that has helped me. This thread is very valuable to me and it has a lot of information so I'm gonna keep/save this link/thread in my computer for future reference. If there is more info that I'm missing or should need please someone let me know. Otherwise I think I'll be alright with all these instructions.
Yes, I found my Product Key (number/sticker) underneath my laptop (it is safe and taken care of now). And thanks for all the helpful links and suggestions.
As of now, I've made backups of these:
1) HP system recovery discs (4 discs so far).
2) create system repair disc.
3) download Win 7 Home Premium x64 ISO via mydigitallife.info
4) found/stored my Product Key
Again, thank you all for your helps and supports.