Yes, but it's not recommended. It's there so you don't have to insert the CD when Win2k needs a file, like in 98.
If ya need more space, buy another hard drive.

I dont a new hard drive, just i have a 3GB C:\ Partition and was just wondering if it was ok to do if i needed space on my windows drive...
 
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1.2Ghz @ 1.32Ghz AMDK7 Athlon Thunderbird
512MB PC133 Hyundai RAM
ATX Gigabyte 71XE4 Motherboard
40GB Seagate ATA/100 5400RPM
16x 10x 40x LiteON ReWriter
40x Compaq CDDrive
17" NEC Monitor
64MB Nvidia GeForce 2Mx
Ambient 56k V.92Fax Modem
Creative 128PCI Soundcard
Hauppage WinTV Card with Radio
EPSON 580 USB Printer
BlackWidow 648HOME USB Scanner
Windows2000Professional SP2 IE6

I'd leave them there. In the event that the files in the WINNT directory got corrupted, Win2k would look to the service pack files to get an uncorrupted version.
It's probably in your best intrests to just leave them there.

Also in situations requiring the installation of a service pack that direvtory would be needed. I don't think MS lists the situations since they don't want you to remove the directory. If you look at the situations that require a reload of a SP in NT then you'll get the picture.