First of all take backup of your catalog on external HDD/DVD (so that you can restore it on another new PC). For doing this please follow- http://help.adobe.com/en_US/elementsorganizer/using/WS3d021fd412237a2f 14afb0171392eec10c6-7ffe.html
After taking backup, switch to new PC and install PSE on that. Once done, please restore the catalog, so as to get all photos/tags/albums that were present on your older PC. Let me know if you stuck somewhere.