I also had these problems, that started with simply copying files "on the machine".
Much slower then under XP. Does it make a copy for NSA under the hood (Restore Point,Old version)?
Also the "I delete 100.000 files and the OS gets very slow" problem still exists and is even worse.
The the network problems - not just under Win 7 - but under Win 8 its even much worse.
The Internet speed is OK now. The speed in the LAN ... i got it fixed with Win 7, but Win 8 ist still slow, slow slow.
I just use this "8" for testing, the rest of the time, the kids from my brother use it for gaming, thats what itsreally good for.