Well... first thing I would suggest is to fix your YSMenu -- You shouldn't have two folders.
Best solution IMO is to back up your skin and YSMenu.ini (if modified) then delete the TTMenu and YSMenu folders, _DS_MENU.DAT, TTMENU.SYS and YSMENU.ARP files
Then build a new YSMenu using
a2h's YSMenu Generator or
R4YSAuto and be sure you get DSTT 1.17a07.
I highly suggest a2h's YSMenu Generator since it comes with DSTT 1.17a07 and has a more friendly interface. You can ignore the infolib.dat part, as you'll be manually updating it later from the
place I linked you to earlier.
After you build you should end up with one folder (TTMenu) and _DS_MENU.DAT which you will copy to your card.
Now, make sure you have your infolib.dat, extinfo.dat and savlib.dat files updated from here:
http://gbatemp.net/index.php?showtopic=194103
Last step is to get your updated USRCHEAT.DAT file from
http://cheats.gbatemp.net/forum/viewtopic.php?f=7&t=239
Oh, I forgot... In YSMenu there is no 'Press Y for Cheats'.
When a game has cheats you'll see a 3rd checkbox appear with a button. It looks like this:
[X] DMA [X] Reset [X] Cheat [...]
The "[...]" will show your cheats.
Even if you get it working now, I'd still suggest you either follow the above steps, or copy all the files from your YSMenu folder to the TTMenu folder and delete YSMenu folder. For some reason, YSMenu works from the YSMenu folder, but games don't like to run properly.