The oil light is just level, not pressure. It's perfectly normal for it to light. I've seen mine come on even in 4th gear acceleration(especially if going uphill), and oil level is perfectly fine, as is the pressure.
As for the "o-ring", you can either:
-Ignore it. Many people have gone 100k+ miles and never had problems, even with "popped" rings".
-Drop the oil pan and check. This requires removal of the exhaust. Not a huge issue, but kind of annoying. There's several "fixes" available.
-Install an
oil pressure kit from Tom at Cycle One Off. They install in 15 minutes and are very nice quality. I was contemplating this issue as well, and decided to check my pressure by installing a gauge. I found my oil pressure was fine (even a bit higher than it seems the normal is), so I left it alone.