Windows 7: A question about the Microsoft Update Catalog x86, x64 and just 7?

I notice that some of the updates are for x86, some are for x64 and some are just Windows 7. If the architecture of the update is not specified then I am assuming that it is an update that should be applied for both architectures. Also my system happens to be x64 so I am not downloading any of the x86 updates. Would the x86 updates even apply to an x64 system or would that be problematic?

Windows Update should only give you updates that you need.
Are the x86 updates for MS Office, and you have Office 32bit?
It might help if you post a screen print of the x86 updates you are not downloading/installing.

This is actually in regards to slipstreaming. So I downloaded a bunch of updates and slipstreamed them in with RT Windows 7. So what I did then was to choose only the Windows 7, & x64 updates. Also I am wondering how prerequisites are handled in regards to slipstreaming. How does the update know that the required prerequisites are installed or do they just install anyway?

I haven't setup a slipstream install, so i would only be guessing at this point.
Hopefully someone who has done this will post here !

I didn't bother with any of the .NET 3.51 x64 updates since I think the idea is to go to .NET 4.0 so I only slipstreamed in the .NET 4.0 x64's. I chose all the updates chronologically after SP1 since my OEM disk already comes preloaded with SP1.

Slipstreaming does NOT work the same way in windows 7 as it did in XP - what are you trying to achieve?

I am trying to achieve a fully updated system. In other words the installation from DVD has the updates slip streamed in. All of them that will be need from an OEM 7 Pro DVD that comes already with SP1. I tried the slip streamed disc and it did install and I did get it fully updated but I see that three updates did fail. I checked again by using the original OEM DVD to install again this time without slip streaming. The result is exactly the same three updates fail. I would be happy to send over the KB's if that matters at all. I am a bit curious why those would be failing. I like the RT Windows 7. It seemed to do the job but I did have to still run the windows update tool and install them...

Which three are failing? (almost certainly .NET ones?) What error message are you getting for them if you look in Update History?

Slipstreaming in WIndows 7 actually restricts what can be done with the resulting disk - you should create an image, rather than slipstream, for backup/reinstall purposes.

KB15597,KB2544521,KB2703157,KB2598845. There is a screenshot attached.

They've only failed once - have you attempted to install them again?
Quite often updates will fail because they must be applied to a previously installed update.
Try updating them againand make a note of the exact error message you get (if any!) when they fail (if they do)