Mac not turning on properly

Would this question qualify to be relocated to newer Mac OS X or macOS area?

If so, which system and configuration of Mac hardware would be most likely...?

Snow Leopard 10.6.8 has a few things going for it, even now.

If the mac still uses system DVDs you could try start-up from disc #1 and run

Disk Utility, or see what may be wrong with the hardware. Could be missing

parts of the system.

If the mac is of much later vintage and has 'internet-installed macOS' then

the question could be moved to later version ASC for better address of issue.

The processes to address these issues, changed significantly over those years.

Good luck & happy trails!🌻

Unknowns include whether or not the install DVD is an original Snow Leopard 10.6.x (OR earlier Leopard 10.5.x)

And whether or not your MacBook shipped as Early, Mid, or Late 2009 build model year configuration.

..Either Mac OS could have been included, as official part number DVD in kit; when it shipped new. An older

white MacBook 2009 included earlier Leopard 10.5. on official DVD media install-restore software. And if so,

retail SnowLeopard 10.6.3 (not grey label) is used as start-up, with included Utilities; useful to troubleshoot.

However if the MacBook had been upgraded to later internet-based installed system, there may have been a

Recovery partition added to the hard drive ~ if so, this may (or not) allow boot into macOS Recovery; in later

system, such as El Capitan 10.11.6 or maybe Yosemite 10.10.x.

So if for some reason the optical drive was unable to start from the disc media; or if the system is newer than

that on those optical media installers, that may be a cause of this issue. An additional troubleshooting layer.

More details as to what you have, and resulting secondary results, are required to continue along this line.