Normally Photoshop start-up time is always little high, if you have many plug-ins installed it can be higher. using Photoshop speedup you can increase the speed by disabling some of the plug-ins, which you can load when you need. It is a free product from Acropdf.
From the website
Adobe Photoshop SpeedUp significantly decreases the time it takes to load Adobe Photoshop by disabling the plug-ins that you may not need. There are several options such as whether to load the Adobe fonts, load the presets, and set the memory usage. You may restore to the original settings at any time. Adobe Photoshop SpeedUp is freeware, works with Adobe Photoshop versions 3 through 8.
read more and download
This page contain another utility which will increase the PDF reader startup time the product name is PDF speedup.
From the website
PDF SpeedUp allows you to significantly speed up the time it takes to load Adobe Reader. If you notice that when the Reader starts it loads many plug-ins which you may or may not need, this program simply disables the plug-ins and loads only the absolute necessary ones so the program starts quickly.