First of all ur description indicates that u have not flashed custom recovery...instead u flashed custom rom directly over stock firmware...That would be extremely dangerous.
Now that you've stuck at boot screen, you must :
* Revert back to stock firmware by flashing it via Odin, then,
* Root ur phone(optional) : not required if u use Odin to flash custom recovery.
* Flash custom recovery: u can find one in this s5830 forum.
Note that s5830 & s5830i(or any alphabet appended) are completely different from each other. You should only use roms, recovery or firmwares intended for ur respective model…
* Now wipe data/cache/dalvik & /system
from this new recovery u just flashed in order to install a custom rom.
* NOW u can flash custom roms.
Pls. also note that roms like cm11 require u to have a certain specific recovery...so be careful
For any other instructions, see the particular rom/recovery thread.
Hope this helps...!!