Kona, there should be noise reduction in ACR. The Develop engine in Lightroom is basically ACR with a different user control panel. In Lightroom, it's in the section called Detail and is below the Sharpening sliders. I think it is labelled the same in ACR. Sharpening and noise interact with each other - excessive sharpening accentuates noise in the image. The following is a good quick summary of how to sharpen and apply noise reduction and how they interact:
Using my K-x images, which should be much the same as you get with your K-r, a typical set of Sharpening and NR settings I use at 800, 1600 and 3200 ISO are:
Sharpening ISO800 ISO1600 ISO3200
Amount 60 55 50 <<I'm a little more aggressive than some with Amount, but offset this with fairly strong Masking>>
Radius <<subject dependent - 0.7-0.8 for landscape fine detail, 1.0-1.1 for general images, 1.2-1.4 for architecture, statutes, man made items, etc >>
Detail 50 40 30 <<candidate for fine tuning image by image>>
Masking <<subject dependent - whatever is needed to stop sharpening being applied to plain surfaces, eg car panels, window glass, plain sky, painted walls, maybe 20-60+%.
Hold down ALT while using to see what is being masked off from the Sharpening tool. Black is being masked. In fact holding down ALT while moving any of the
Sharpening sliders allows the effect to be evaluated - very useful.>>
NR ISO800 ISO1600 ISO3200
Luminance 35 50 65
Detail 50 40 30
Contrast 50 50 50 <<I find this adds good micro-contrast>>
Colour 50 70 80+ <<cutting colour noise doesn't degrade image detail much so can be a bit aggressive here>>
Detail 50 50 50 <<LR default value, don't play with this much at all>>
Hope you can interpret the above, I don't know how to format tables in this forum's software - repetitive spaces are stripped out.
These are LR3.6 settings, I haven't upgraded yet to LR4 so don't as yet know if I need to revise my approach.
These are varied as needed for individual images but are my starting reference points. I set each up as Presets, eg I have an ISO800NR preset which I click on and all the above settings for ISO800 are immediately applied. I can then fiddle with this if needed. Makes it very quick to get close to right straight away. After setting sharpening first and then the NR, I sometimes find the image is too smeared and detail lost, then have to go back to Sharpening and maybe reduce sharpening a little further or apply more masking, and then reduce NR until a bit more detail re-emerges. Once you get the hang of it, getting high ISO images about right can be done quite quickly. My one golden rule is: AVOID UNDEREXPOSING IMAGES TAKEN AT HIGH ISO. Every stop of positive exposure adjustment is equivalent to a stop increase in ISO. Eg, an underexposed image taken in ISO3200 is really the same as an image taken correctly at ISO6400. This is why I emphasis using the histogram in the camera when playing back a shot just taken to ensure the image isn't biased towards dark tones. Immediately retake if it is.
By way of example, this was taken on the K-x at ISO3200 during last month's Single in... challenge:
Amount 53 Radius 1.4 Detail 41 Masking 47 Luminance 58, Detail 34, Contrast 52 Colour 100 Detail 50
And this was with Exposure having to be increased +0.84EV in PP as I was drinking at the time and not paying too much attention to what I was doing
so was broadly equivalent to a well exposed shot at ISO5900 or thereabouts.