i remember you asking about rooting or custom rom
for you rooting is much simpler..to install what you want
for installing custom rom you need to do full wipe ..which will cost you your data (of apps) and sms , contacts and call logs
but custome rom gives you huge advantage over stock rom...your UI will be much smoother...and there are tons of optimizations...which is a huge plus (like camera/video is awesome after a mod...which overwrites the stock HTC junk camera/video)..
if you want custom rom..
i recommend you to install super backup app through which you can backup sms contacts and call logs
then install a custom rom (see my signature for the current rom im using) via recovery
PS: there is a way to say thanks in XDA