I have Photoshop 5.0 also. I have tried a few different things just by winging it. One was to cut and paste the object (Viper) into the picture I wanted and then "erase" the surroundings in the pasted Viper picture (2nd layer). It's kinda cool to watch the background "appear" from the first layer (background). Then I "flatten image" in order to save it as a jpeg vs. the psd format of Photoshop. Again, I am also a novice and have no manual. I have learned by experimenting and consider myself to be fair, but not necessarily great. Good luck!
Chris
PS. And since this is more of a software topic vs. Viper topic, I will respectfully move it to Off Topic. Thanks!