A lot of people still use Adobe Reader to open PDF fomat file without realizing that they can actually use more light-weight application to open PDF file. Yes, Adobe Reader is really heavy and need long loading time.
If your main purpose is just to read content of the PDF file, I really suggest you to try Foxit Reader.
Not only Foxit Reader loads faster than Adobe Reader, the installer size is also small compare to Adobe Reader.
For your information, Foxit Reader even run well on my PC that is just using Pentium 4 processor. And the best of all, Foxit Reader is free to use. No crack is needed. Voila !
If you wish to use Foxit Reader, you can download it at Foxit Software web site.