Erase and reset are basically different procedures. If you want to erase, then you must use disk Utility, if sensitive data are implied to zero all data. This means to effectively remove data from your disk.
If you want to reset, you may simply create a new user with admin privileges, log into that user, then delete old admin user. This latter action does not delete sensitive data, but may be sufficient if you want to start using mac from the scratch.
Link suggested by shldr2thewheel is also good, especially if you want to sell your mac.
I've been reading posts about how to get a macbook pro ready for it's new owner...just one question.
Our macbook pro is a 2006/2007 model, 2.16 GHz, Intel Core 2 Duo, upgraded memory to 3 GB, and running 10.7.5. I realize we're not getting rich with selling this computer, but I'm thinking we could get something out of it.
If we follow the directions above, will it no longer be running 10.7.5? If not, what do we do so it is running 10.7.5 when/if we're able to sell it?
1.Your model will accept Lion (10.7.5), but not Mountain Lion (10.8.x). Mactracker will tell you more, a free dabatabase of all Apple products.
2. mac2sell.net will give you a rough estimate of the average price you may get for it, +/- 10–20 % depending on details like battery life, scratches, dead pixels etc.