You should be able to copy your My Library folder and all contents from your old machine to the new one, then when you install D|S on the new machine make sure the content folder points to wherever you put your old My Library folder. The only things you will have to re-install are the extra plugins that don’t come as part of the D|S download: these depend very heavily on exactly how and where the D|S files are installed, and it is very rare for them still to work properly after a straight folder copy from one machine to another.
Note that this folder may be slightly huge, it contains all the data for every model you’ve installed, all textures, morphs, saved scenes, etc.
For example Duarte Hair has a seperate installer for trx.exe, metadata.exe and dpc.exe.
Why on earth cannot the people get this all under one installer for each product anyhow!
Depending on which programs you’re using, you might be able to ignore some of these. The metadata installers only replicate the metadata (used for the Content Management System) in the main installers. You can usually ignore them, unless there is an update to the metadata and downloading/installing the smaller file is faster and easier than doing the whole thing all over again. It seems the separate metadata files are now being phased out, so this might not be a problem in the future. (You can also ignore them if, like me, you don’t use the CMS.)
Anything “trx” is (or should be) a Genesis character, hair or clothes file; always run this file if you’re using D|S 4.5.
The “ds” files are also for D|S but not necessarily for Genesis, they might be an older non-Genesis figure, a prop, scenery or a texture set.
The “dpc” files are for Poser: if you have Poser as well as D|S then run this file as well. You might also need it in D|S, as many installers have the actual model in Poser format in the “dpc” installer, and only D|S materials files in the “ds” installers. If this is the case, the “ds” file will be much smaller than the “dpc” file. Usually (unfortunately not always) the store product page will tell you if the Poser and D|S installers are each complete and self-contained, or if you’ll need both.