Computers will need more than ample RAM for WGT, 4Gb as a minimum.
Apart from the general PC maintenance - (use CCleaner) - thin out your start up entries etc
dryspot:click on advance see if your backgrounds are unchecked.
Check Background Loading is ON.
This loads the next hole while you are finishing the current one. The 'Continue' button on your scorecard at the end of a hole will appear faster.