Trouble w/ mysqldump

[Hurrican19]

Hi All,
I run a website, and am having a problem w/ corrupt databases..

I was runnig MySQL v3.23 previously, and my db dumps worked fine .. However, I have since
upgraded to v4.1.8a-log and I am having problems getting completed (or non corrupt)
backups.. The problem is pretty big..

My Original Backup of the DB using 3.23 was 208MB --- When I upgraded to 4.18 the backup
is only 138MB ... My users Avatar's, all attachments, etc are totally whacked out. Does
anyone have any insight on what is causing this, and how to fix it? Any help is
appreciated.. I need a new good backup desperately