I wonder if it is due to the fact that I don't have enough memory left on my 2GB miniSD card or if the game itself just can't save. Yggdra Union freezes whenever I try to save in-game Sword of Mana tells me "unable to save data" when I try I guess I will have to play these games using savestates, which I don't feel comfortable about. Do GBA game saves take up a lot of memory?
Based on your sig I'm going to assume you are using an M3 MiniSD: How are you putting the games on your card? If using the gamemanager try copying them over without using the gamemanager, and also grab the blank save file from the M3 folder in Program Files and copy that to the GAMESAVE folder on the card, rename this save file so it matches the GBA game (eg. "SwordofMana.gba" would have a save file "SwordofMana.dat") Do you have this problem with all your GBA games, or only some of them?
Only some of them. Most of the games save fine without problems, I think it is because there isn't much room left at all on my SD card is the problem. I'm going to check the card next time I get near some USB 2.0 ports (USB 1.1 at home)
