Main thing I do is change the prefetch settings.
Open regedit, navigate to the key:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Contro l\Session Manager\Memory Management\PrefetchParameters
Change "EnablePrefetcher" to value 2. (It should be 3 as default)
Then browse to C:\Windows\Prefetch and delete all .pf files. Leave all other files in place.
Other than that do a Ccleaner scan on the registry and clean up anything found. Remove un-needed startup items.
Should get it fairly nippy.