I believe the forum you need to post your queries is either Application Server,DB and OS platform etc and not this forum .Please do so in future .
Coming to your queries,
http://help.sap.com is a wonderful link where you can get information of most of the things of SAP.
1.Work load analysis--- please search the above link by workload analysis
2.What is logon load balancing-please search the above link by logon load balancing
3.SM36 and SM37 are the two trasactions where you can maintain jobs ,monito rthem and so on .There can be many reasons for a job to get failed.First point is to check the job log.Can you quote any instance where some job has been failed so that i can try to help you out