Windows 7 - Load times (the moments after clicking icon)

For example, when I click the WoW.exe icon for world of warcraft, after a fresh install of windows 7, it seems like only takes a few seconds for the password screen to popup and few seconds to be into character select.

Six months later it seems like it takes three times longer.
I've been building my PCs myself for almost 20 years. Starting with sound blaster sound cards back in the day of manual jumpers.

My hard drives only half full, It automatically defrags weekly at 2am, zero% defragmented on the report. (300+ gig hard drive) 4 gigs ram 512 on the video card 9800nvidia.
win 7 64bit, 2.7ghz dual core.

No signs of spyware or virus (of the years ive delt with the new types and removing it, or better yet, reformatting).


What could cause these seemingly slower load times?

I would not say that it takes all that much longer for the actual load chunk progress, for example, zoning into new areas, or loading into the zone for the first time.
That might take a little longer, but nothing drastic.

I just dont understand why it seems to take twice or three times longer to get from the icon click for displays to start appearing.

I would guess "registery trash". I dont know much about registery.
I dont install tons of stuff, I try to never bother with any browser bull @#$ addons.

I even disable Aero in Windows 7 just for the extra framerates in game.

Could be due to an anti virus program or spyware program or just due to programs running in the back gound such as Windows update or other updates.