Hi eddien4 and welcome.

No this is not normal.  Have you run a full anti-virus scan?

Unfortunately, this problem can be caused by lots of things and can depend on what software has been installed.

The most usual cause, other than a virus infection, is that the Vaio is searching for links to software, services or drivers that no longer exist, have been moved or not fully uninstalled.

A software/driver conflict is another possibility as is a heavily fragmented hard drive or the system paging large amounts of data to the hard drive.

Two suggestions: -

1. Download a 30 day free trial of a Registry cleaning program to remove any incomplete or broken links.  Run the utility to remove junk files.  I would leave the hard drive defragmentation for now as this may take a long time to run on such a large hard disc.  I am reluctant to recommend software of this sort as it can occasionally cause problems but I use System Mechanic.

http://www.iolo.com/system-mechanic/standard/download.aspx

Alternatively, try a lightweight, free cleaner like CCleaner: -

http://www.filehippo.com/download_ccleaner/

2.Back up the files and data on the Vaio and restore the system back to factory settings using the Recovery Guide here: -

ftp://ftp.vaio-link.com/pub/manuals/consumer/2011Q3_TRG_EN.pdf

You will have to set it up again from new but this gives you an opportunity to load software one at a time and see if one particular program is causing the issue.