First make sure you have USB 2.0 enabled in the BIOS Setup menu - sometime called 'Hi-speed'.
Some BIOSes have very slow USB drivers. You can try to use the grub4dos driver instead.
Boot to E2B
Select the grub4dos 0.4.6 driver menu entry
Select the load USB 2.0 driver menu entry
Now press F8 - is it now a lot faster? If so then your BIOS has slow USB drivers.
You can enable 0.4.6+USB driver support by changing the MyE2B.cfg file. However, the 0.4.6 USB driver is not 100% reliable and you may have problems with some systems (or it may work for your systems).
P.S. The other thing you may prefer is to enable FASTLOAD. See the \_ISO folder for instructions and this site.
Subject Re: E2B running EXTREMELY SLOW