I'm sorry ....... THIS QUESTION IS NOT RELATED TO NLITE IN ANY ASPECT ..

i know that Recovery Console can be accessed via Windows XP SP3 CD on Windows XP Operating System with out SP3.

In case i replace some corrupted important system files with the ones in Windows XP SP3 CD using R Console, the file version of the system file will be new. Will it function properly ?

lemme give an EXAMPLE ..... if i replace the old explorer.exe with version
6.0.2600.0 (without any SP)
with the new
6.0.2900.5512 (SP3)
.... will i hav any problems ? this is just an xample ... i am asking u in general for all system files that usually get corrupt like NTLDR, NTDETECT.COM, shell32.dll, msgina.dll, winlogon.exe, cmd.exe etc .....

Most likely, tho how severe is a better question imho.
Tho if system is unusuable and there a no other options, you do not have a choice do you? Either that or a reinstall, if no backups are available.