Atra du evarinya ono varda.
Convenience plus decent usability might be something that you are looking for based on your descriptions. If this is so, go for the first option: the $150 digicam. You could bring it everywhere with you and conveniently snap a quick moment as compared to the other options where you have to set up equipment which sounds rather time-consuming and complex and might cause you to miss that perfect moment.
On the other hand, if you are looking for a camera which takes better quality photos, go for the Olympus or the old film Canon. I'd say that the quality of the pictures compromises for the inconvenience and bulkiness of the equipment and other required set-up materials.
In the end, it's your choice. Just go for what you think suits your needs the best and you'll be all good to go. :)