Surely not uninstalling.
How do you zoom?
Perhaps try with the navigator panel, top left panel in develop or library single image = loop view.. There you find some ratios, among them 1:1, also other. You can define your own as well by clicking on the drop-down triangle. The system will remember which zoom ratio you used last if you just click on the photo. Spacebar will toggle between your last few ratios.
Could you explain more exactly what you mean by "100%"? If you have clicked on the 1:1 option, LR will toggle between that and "Fit" when you click. If you have clicked on another option, say 8:1, LR will be instead toggling between that and Fit.
Some people think of "100%" as meaning: I can see the whole picture - though this is not the convention - something LR tackles with "Fit" and "Fill". These options should work in an obvious way, but if they do not, it may be that LR has not yet generated the needed previews. In that case you may merely see a crude enlarged version of a very low-resolution thumbnail when you zoom in - something that gets replaced with the full detail of the image in due course.
If you are getting multiple images displayed overlapping, that sounds like a graphics display driver problem, would be my next guess - good idea to check if the latest available version is installed. Or your computer lacks the processing power to refresh fast enough, or its graphics acceleration features are not being used for some reason.
If the cropped or actual pixel dimensions of your image are less than that of your display window, then Fit and Fill will never enlarge beyond what 1:1 does; they only reduce. 2:1 would still double the size, 1:2 would halve the size, etc.
The zoom factor options do not give a standard percentage view of the image - depending both on the pixel count of the image and the pixel count of your screen. Those who are not used to evaluating pixels in this way are often slightly shocked by the apparent bad quality, of an image from a higher-resoiution sensor as compared with one from a lower-resolution sensor. This despite being perfectly good in whole-image terms... it is a magnification effect - in the same way that the smoothest surface looks fine under an optical microscope, but like sandpaper under an electron microscope.
Also many people become used to conceiving their image in physical terms (for example, as if it were a print of a certain size in inches) and in that case, they may seek a "print size" zoom. LR does not offer such a feature, because all the images seen are completely output-independent and have no one size assigned to them, of the kind that Photoshop deals in - a 1:1 zoom will always look much larger than such a print-size zoom would.
Thank you for the in-depth response. I am not talking of using the 1:1 ratio and I do understand how "100%" zoom works as well as any of the other percentages or aspect ratios. When I say it "zooms in past 100%" what I mean is, after I click any form of zoom (whether from the presets, the drop-down ratio bar or the slider) the program zooms in uncontrollably in increasing layers until only a tiny sliver of the photo is pixilated. I am not talking a 100% zoom with a low resolution file, I am talking about zooming in on one leaf in an entire forest until it fills my monitor. My files are not a low resolution and the thumbnails should have had more than enough time to generate and are all good as they have all been viewed and worked with in CS5. I would not think that there is a problem with my graphics driver as this is the only program being ran on a brand new pc which I bought for organization and editing only. The laptop uses AMD Radeon HD 6320 graphics (I am not the most savvy with computers... but I assume this is sufficient) and I installed LR4.1. Do you think there is something wrong with the computer? I would not know where to begin if that was the case, but I am very curious to find out what the problem is. If it is just a matter of something being a little off in the download, I could easily just uninstall and try to reinstall again.
Oh! One more thing... this problem seems to only happen when in the "Develop" interface. While in "Library" the ratios work correctly.
I can't offer much more, than to repeat the suggestion that you check for updates of your graphics card driver - even a brand new computer is not always supplied with the most recent version installed.
Otherwise, you might try making a fresh catalog and importing a selection of the same images into that - these will at least start out "clean" in terms of the previews etc. If the same problem repeats there, then perhaps you have a corrupted installation of Lightroom.
That sounds like a graphics driver issue to me too. Could you tell us your system specs, perhaps? The laptop model number would do, we can look up the specs from there.
That said, if it turns out not to be graphics driver, what mouse are you using? Things like logitech and microsoft mouse drivers have created similar weird behaviour in the past.
I guess I am going to look into what could be wrong with my graphics driver. This laptop is an Acer 5250-0639 with AMD Vision E2 dual core, Windows 7, AMD Radeon HD 6320 graphics. This is the only installed program on this computer, so I cannot say how it works with anything else like CS5 or 6 or an older version of lightroom. I believe the computers I have CS on are similar in power as they are toshibas and dells that are one and two years old. The mouse I use with the Acer is a Gear Head wireless mouse at 2.4 GHz. I took the mouse out and the problem remained. How would I go about looking for a graphics driver update?
Well, I tried the graphics driver update and downloaded AMD Catalyst (which was the only thing available as an update for me). This did not fix the problem. I am really at an end for my computer diagnosis knowledge and really would just like to uninstall the program. I am using the 30 day trial (thankfully) and was wondering if I could uninstall and Adobe would allow for me to install again. Any thoughts on this or any other action I could take?
I sympathise with your difficulty, not sure what else to suggest right now. Mouse driver maybe. Disable graphics acceleration settings. Run program in Compatibility mode? Im just guessing now.
Once the trial period has ended, that is that for ever using the software under a trial basis for that particular computer - even if you completely uninstall and reinstall - for that specific version. The software will install OK but you will not get past the "trial or buy" screen unless/until you buy a serial number. I am not sure what Adobe can do to help you otherwise. So any further testing or fiddling you can do now, while the trial is still running, will at least give you feedback on whether it has worked or not.
However the subsequent version (or a prior version) can be trialled, for the full period, on the same computer - since each LR version is a full, independent installation.