I am on a Cable connected Modem, with a wired/wireless Router. There are 6 desktops and laptops connected most of the time. Then have two other laptops that are sometimes connected. There are 2 printers connected to 2 desktops, and 3 scanners connected to 3 desktops. The printers are all shared to ALL connected by wire or wireless for use.
We have a mixture of Windows 7 32 and 64 bit, XP and sometimes Windows 8. Files are also shared across the network on most of the machines.
As of yet I have not had any memory errors on any of these machines and I run several different versions of FTM on 5 of these machines. I do a lot of testing of OS's and programs.
So I do NOT think that your network is at issue other than maybe the "Apple" products that you have running. I have seen many times when some of these "I" products are at fault.
The "Svchost.exe " is used by many devices, processes and programs. So you may see it listed many times. I have not seen any issues as to these slowing down a system other than it can get damaged. See http://www.exe-error-advisor.com/svchost-exe
for more information.