I discovered that i have choroid plexus cysts at 33 yrs old. what the likely hood early onset of dementia, parkinson's, or any neurological disorder?

Adult cases are rare: I understand that this is fairly rare in adults and neurologists suggest monitoring to observe cyst growth/changes, but expect it to be benign. It's difficult to ignore those reports by patients who discovered them upon symptoms of early dementia - but they might be unrelated. Even experts are working hard to understand these conditions. It's stressful and challenging to patients, but try to relax.

If no obstruction: None. As long as productions of CSF is normal and there is no CSF obstruction you should do fine. Some people will require a shunt at some point.