...anyway, here's what you do.

From a guy who knows 2000 by heart.

Expand both 2000's and XP's SYSSETUP.IN_ file.

Go to [infs.Always]

See all of those INF entries? Let's compare.

wsh.inf,DefaultInstall
ie.inf,DefaultInstall
secdrv.inf,DefaultInstall
mdac.inf,DefaultInstall
icwnt5.inf,DefaultInstall
mstask.inf,DefaultInstall.NT
msoe50.inf,DefaultInstall
wab50.inf,DefaultInstall
tshoot.inf,DefaultInstall
dfrg.inf,DefaultInstall
msinfo32.inf,DefaultInstall
axant5.inf,DefaultInstall
msnetmtg.inf,DefaultInstall
mplayer2.inf,InstallWMP64
sr.inf,DefaultInstall
fltmgr.inf,DefaultInstall
icminst.inf,DefaultInstall
apcompat.inf,DefaultInstall
shell.inf,DefaultInstall
shl_img.inf,DefaultInstall
netupnph.inf,DefaultInstall
devxprop.inf,DefaultInstall
syssetup.inf,SpecialInstall
pchealth.inf,DefaultInstall
oobe.inf,DefaultInstall
sapi5.inf,DefaultInstall
moviemk.inf,DefaultInstall
qmgr.inf,DefaultInstall
au.inf,DefaultInstall
skins.inf,InstallSkins
drm.inf,InstallDRM
wmdm.inf,InstallWMDM
wmfsdk.inf,InstallWMFSDK
wmp.inf,InstallWMP7
wmtour.inf,DefaultInstall
mymusic.inf,InstallWMPlaylist
syssetup.inf,WMPFeature
swflash.inf,DefaultInstall
dimaps.inf,DefaultInstall
vgx.inf,DefaultInstall
srchasst.inf,DefaultInstall
bthpan.inf,DefaultInstall
netfw.inf,DefaultInstall

Here is the list from Windows 2000, and I comment out those INFs that I personally do not use:

ie.inf,DefaultInstall
mdac.inf,DefaultInstall
dfrg.inf,DefaultInstall
rsm.inf,DefaultInstall
mpcodecs.inf,DefaultInstall
icminst.inf,DefaultInstall
agtinst.inf,,DefaultInstall
spchapi.inf,,DefaultInstall
shell.inf,DefaultInstall
;axant5.inf,DefaultInstall
;icwnt5.inf,DefaultInstall
;amovie.inf,DefaultInstall.NT
;wbemnt5.inf,DefaultInstall
;mstask.inf,DefaultInstall.NT
;msoe50.inf,DefaultInstall
;wab50.inf,DefaultInstall
;tshoot.inf,DefaultInstall
;msinfo32.inf,DefaultInstall
;msnetmtg.inf,DefaultInstall
;mplayer2.inf,DefaultInstall.NT
;rstorage.inf,DefaultInstall.NT
;apcompat.inf,DefaultInstall
;rca.inf,DefaultInstall
;wmpocm.inf,DefaultInstall.NT
;syssetup.inf,SpecialInstall

I don't have the time to detail the XP INF files, though I happen to know most of them, but I think Google will help. Also, you can look at any of them easily to see if you "need" them by using "expand -r filename.inf"

Hope this helps

Syssetup.inf is digitally signed in Windows XP, so syssetup.dll has to be patched so as to check for M$ Digital Signature on the syssetup.inf file, flagging it as "Always Valid" so that it can be modified.  Here are the entries I made for a RVM integrator addon:

File name         File version  Offset BeforeHexCode  AfterHexCode
I386\SYSSETUP.DLL|5.1.2600.2530|210500|	    73       |    72  		;SP2
I386\SYSSETUP.DLL|5.1.2600.2659|211108|     73       |    72  		;KB894871 - SP2QFE
I386\SYSSETUP.DLL|5.1.2600.5512|211753|     73       |    72  		;KB936929 - SP3

To remove syssetup.dll from SFC monitoring I patch sfcfiles.dll thus:

File name         File version  Offset BeforeHexCode  AfterHexCode
I386\sfcfiles.dll|5.1.2600.5512|218048|   250073     |   5C0000     :syssetup.dll
I386\sfcfiles.dll|5.1.2600.5512|522176|   250073     |   5C0000     :syssetup.dll 
I386\sfcfiles.dll|5.1.2600.5512|843936|   250073     |   5C0000     :syssetup.dll 
I386\sfcfiles.dll|5.1.2600.5512|1180888|  250073     |   5C0000     :syssetup.dll 
I386\sfcfiles.dll|5.1.2600.5512|1494120|  250073     |   5C0000     :syssetup.dll

Sfcfiles.dll is also subject to SFC momitoring so it has to be patched thus:

File name         File version  Offset  BeforeHexCode  AfterHexCode
I386\sfcfiles.dll|5.1.2600.5512|15024  |   250073     |   5C0000    ;sfcfiles.dll
I386\sfcfiles.dll|5.1.2600.5512|307384 |   250073     |   5C0000    ;sfcfiles.dll
I386\sfcfiles.dll|5.1.2600.5512|629144 |   250073     |   5C0000    ;sfcfiles.dll
I386\sfcfiles.dll|5.1.2600.5512|966096 |   250073     |   5C0000    ;sfcfiles.dll
I386\sfcfiles.dll|5.1.2600.5512|1291096|   250073     |   5C0000    ;sfcfiles.dll