you have 2 options:
option 1)install factory signed software. download this file and run it as administrator. follow the onscreen directions and plug in your phone when directed.
FileFactory Premium
be aware,that it will overwrite your custom recovery,so if you wish to remain rooted,we will have to re-install your recovery afterward,wich is not a big deal as long as you verify that you are s-off in hboot. it would not be a bad idea for you to post your hboot version and baseband,when you boot to hboot to verify s off.
option 2)simply flash a new rom. there are ICS roms you can try,but im not familiar with any of them,i dont know how functional or daily driveable they currently are.
for a stockish rom with some enhancements,id highly reccomend ARHD,wich is gingerbread with sense 3.0:
[ROM] Android Revolution HD 7.0.4 | High Quality & Performance | O/C | Legendary - xda-developers
its a very nice rom. just do a full wipe and install in recovery as you did your current rom. even tho you dont like your current rom,it wouldnt be a bad idea to make a backup,so you have a working backup of
something,in case you need it.
holler if you have further questions