sounds to me like a brake light switch fault, its not uncommon for these to fail, you will find it on the brake pedal. you will need to remove the drivers kick panel, which involves removing the drivers end dash trim where you will find 4 torx 25 or 27 (cant remember exactly) and also 3 on the lower section of the kick panel. the lighting switch is next to come out, and then the trim should pop off from the top then slide out. the switch will be eaisly accesable from there. The torx bits should not cost a fortune, everywhere sells these now as they are widly used. the job is very simple and can be done in less than half an hour, but i have done many of these....
with regards to your airbag light, you will need to get a fault code read, but your probably looking at either one of your seat side airbags, again pretty common.
hope this was of some help
rob
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