service packs eating up disk space

After having updated my Windows NT 4.0 workstation with sp4, sp5 and currently sp6 i have run out of Disk space out my 2GB HDD.

I have discovered that there are system files duplicated in C:\I386, C:\Winnt\system32 and in
C:\winnt\%NtServicePackUninstall%

Can I delete C:\I386 which contains the oldes files and C:\winnt\%NtServicePackUninstall% which seems to hold files for unistallation purposes only?