Skip to Finity Mode
You can quickly switch to "Finity Mode" without having to grind through the levels of "Endless Mode." Open up a text editing program such as Notepad (go to your "Start Menu" then "All Programs" and access "Applications" to find it), then open up the game's "config.xml" file located in the Bejeweled 2 folder (open your primary hard drive, then "Program Files" to find the game folder). Modify the values of the last two lines of 500 and 150 to 1, and save the changes. When you play the game in "Endless Mode," you instantly clear each level without effort.
Slow Motion
Type in the word "slomo" during gameplay to slow down the movement of gems. Note that by activating this code, your score will not be recorded.
Gem Colors
You can change the gem colors at any time during gameplay. Type in "blackandwhite" and all gems will lose their colors, or you can use "colorswap" to switch gem colors and create easier gem combos. When you want to return to regular colors, simply type "normal" to revert all the gems back to their original colors.