Thanks Saga Lout.
That did fix the problem for a few hours but as I noticed the connection acting buggy again (even though the router was working perfectly) I ran the troubleshooting option and now I'm back to square one. If it helps I noticed the wireless adapter lost connectivity after the troubleshooter reset it.
I checked the BIOS menus and they were unchanged (what originally fixed the problem was switching the "Onboard LAN Boot ROM" option to ENABLED.
I can access the internet via ethernet now and interestingly, when I turn off the wireless connectivity switch and turn it on the message displayed on the screen reads "Wireless LAN OFF" but bluetooth turns back on every time.