Memory card part needs to come out so i can replace it, how can i do this , on a ds lite....

SOURCE: DS Lite unable to read DS game card

try to use rubbing alcohol on a qtip and clean the game connectors and inside the game slot. Or try to blow on it. that usually does the trick

SOURCE: Ds Lite R4 Sd card

the 2nd generation r4s do not use r4 v1.18 kernel goto www.r4sdhc.com download the software from there

SOURCE: nintendo ds lite won't read card

its usually in the menu, change it to ds lite,instead of gameboy.

SOURCE: how to put games in my memory card at Nintendo DS Lite?

To get an in depth answer seach you tube but in brief.
You will need to download the system files for your type of R4 or flash card you are using, make sure you get the exact model type as they are not interchangeable.
Drag and drop the files to your card you will see either 4 or 5 files. Then make a folder called Games on your micro SD card and load your games into that folder.
It quite involved but the tutorials on you tube go right into it.

SOURCE: DS lite does not recognize inserted ds game card.

jvnabc try blowing into the ds and your game