Delay between command and response

Suddenly this computer has developed a delay between command and response. This applies to:
- typing (delay before letters show)
- clicking(delay before click activates)
- any ordinary operations ... opening pages, playing videos, closing browser etc.
This is a recent development and there is no obvious source (ie haven't visited insecure sites)

I have scanned and report is virus free.

Unsure what other steps I can take aside from a total file scan.

Any suggestions?

Thanks mrjimphelps - have done that and found only two non MS items and un-ticked them.

Megahertz07 - what you say feels right ... it all began after an update. Since the laptop crashed completely and I had to restart with rescue disk and then reloaded a system's image. So have lost the latest data.
Would you by any chance have any idea about which DL item it was? Be good to delete it.

DL = Down Load ... probably WD (Win update) should have been used.
Yes, WU now turned off.

I deleted the 3 last WU and so far the system is working properly...early days but looks good.

You know Megahertz07 this is not the first time I've had serious trouble from WU. I used to have MSE (as the anti virus) and
encountered blue screen and total failure due to conflicts between MSW and the WU. Needless to say I never used MSW again.

What gets me is that there is no consumer protection. For example after years of trying to find a solution I still have to put up
with jumping cursor which makes touch typing impossible. MS couldn't care less. To have WU which cause a system to totally lock up (I couldn't restart and had to reboot from REscue disk and re-load recent Image) is just not acceptable.

Thanks for your imput ... it was appreciated.

Good advice...thx. Have just followed suit. Had only changed to Never check.

where do I find SP2 link?