Can I upgrade my 2007 front suspension?
Short answer: Yes easy.

My recommended process:

If you are the original owner of the bike check out SR Suntour's upgrade program.

https://www.srsuntour.us/pages/upgrade

The RAIDON XC-LO-R 26 with a straight steerer would be a really good fork for that bike at $199 down from $299 with the deal.

If that isn't appealing you'll want anything that has support for a 26" wheel, 100mm of travel, and a straight 1 1/8" steerer. I doubt you'll be able to fit anything over a 2.3-2.4" tire in there.

Note: For the fork from SR Suntour I mentioned, it has a 160mm flat mount support for brakes, so you'll probably have to upgrade your front rotor to a larger size as well.