svchost.exe blocking web browsing

I've got the same problem!

When routing the svchost prob, I can find in :

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows
NT\CurrentVersion\SvcHost

the following key:

NetworkService (the one giving 98% CPU load) that
contains the data: DnsCache.

I suppose that the problem would be solved by deleting
that key, though I would first like to know what the
funtionality of the key is before deleting.

I noticed it gives a high CPU load at startup of windows
and at connection on the internet.

any help or clarification would be appreciated.