You must have gotten a low profile 9600GT on accident. Almost all gaming video cards are full height you just got bad luck I guess and didn't notice before purchasing.
What video cards you can use depends on your power supply. What video card you should buy depends on your CPU, your monitor's resolution and your budget. We need to know these things before recommending a card.
CPU is Pentium D 820 (2.8ghz)
Power supply is 364.7 watts
Budget is $100-$150
Thanks for all the help guys, I really appreciate it.. If possible I'd like links to whatever you guys can recommend.