Advice needed on repair of XP

I remember seeing a thread about the effect of the repair procedure from the installation CD on installed updates and SP1, but I can't find this thread using the search.
Recently my XP start-up has become slower and slower with a noticeable delay after the desktop has loaded, and now that I need it System Restore refuses to work. I have tried Bootvis, but get an error message saying that zero drives are recognised! I assume that there is a problem with one or more system files and that a repair is needed.
My XP is SP1 and has had all the recommended updates installed up to yesterday, and the system is functioning very well apart from the slow loading.
My question is - If I carry out the repair procedure from the CD, will SP1 and all the updates stay in place, or shall I have to re-install them all?
If they need to be re-installed I shall try to wait until I can get an SP2 CD!!

 

You would normally lose SP1 and all later updates.

Search on here for threads about slipstream to see suggestions and how-to info on burning yourself a CD with XP and SP1 already combined. It works lots better than loading XP and then applying the SP.

You would still need to do all the post-SP1 updates but you'll for sure have a cleaner running system.