Win7 command processor (CMD.EXE) really slow
instead of using cmd.com, have you tried PowerShell? I believe it's under accessories.
There seems to be a problem with installed keyboard layouts and cmd.exe (at least that's true for my vista machine and some of my colleagues).
Try to remove any additonal languages from "System Settings->Region and Language options->Keyboards & Languages->Change keyboards->Installed Services" (translated on the fly - YMMV).
That reduced cmd.exe startup for me from "very annoying" to "instant".