Question 1. Why such an old version of OS? I would update to Oracle 7.6 or Oracle 8.0
I see ohasd.bin, I assume this is an Oracle RAC cluster member? It looks like that it is having trouble talking to the cluster. Are the other nodes up? Is there network connectivity?
But seriously, if you can update to the 4.14 kernel (or newer)
it handles "hung process" timeouts slightly differently. Also the cpu scheduling won't lock everything else down until those processes are completed.
To start CRS run "crsctl start crs" and then "crsctl check crs" to ensure everything has started.
If for some reason there is an error here, you'll need to fix that first.