2001 L300 lights flashing, starts, but cant get it out of park

Hello, a friend of mine has a 2001 Saturn L300 it has an intermeiate problem that we cant seem to pin point. All the interior lights flash (dome, dash bord, door lights.. everything on the interior of the car) which when it does this issue. It also will start but will not come out of park. It happens about 50% of the time. Last time it had happened she had driven it to the gas station just fine. Then when she went to drive it back home. It wouldnt get out of park. Ended up having to get it into neutral, then start it up so she could drive it back home. We have replaced the alternator, we have a MAF sensor, and an O2 upflow sensor on the way (as per the scanner codes) these will mot help the problems that are causing her to keep getting stranded. We have tried to reset the secerity system several times. Has not seemed to work. I also been thinking that the brake light sensor might be bad but been told that the brake light wouldnt work either, which it does. We have also checked the fuses as well. We are debating on changing out the lock cylinoid (sp?) as per a bad sensor in it?, contacting an locksmith as possible bad chip in the key (but wouldnt this be a constent thing?), maybe replacing the immoblizer, security modular.. any ideas as this is starting to cost a small fortune for her..
Also the car doesnt chime when the key is in the igition with door open..

Thanks for your time and help!