cshapiro-
1) Is this “slow typing” issue a problem in all programs or only in some (e.g, word processor, browser, spreadsheet)?
2) Did this happen suddenly or gradually?
3) Do you have up-to-date antivirus software? Have you run it recently?
4) Do you have up-to-date anti-spyware software? Have you run it recently?
5) Have you started your PC in safe mode and seen if the problem still occurred?
6) Did you recently install new software?
7) Did you recently visit a website that looked strange, suspicious, or asked to install something?
I Googled your problem and the following potential solutions came up (I do NOT suggest you try any of them just yet):
a) Power down the PC, unplug it, remove the battery let it sit for a while, and then power it back up.
b) Run up-to-date anti-virus/spyware software.
c) Make a registry change.
What the above solutions suggest is that your problem may be caused by a variety of reasons.
I’d suggest running antivirus/antispyware programs as a good start.
Before you do anything, please answer the questions at the beginning of this post – something may jump out as the obvious cause.