Help Hero not booting properly..

[SpaceCadet69]

Hi all, my phone is having issues booting up. I turn it on and it gets to the htc load screen then reverts back to the T-mobile load screen constantly and doesn't get any further. yesterday it was displaying that my memory was running low and that I needed to delete some app's...which I did. This morning I was having problems connecting to the internet so turned it off to turn it back on again when the boot problem started. Please could anyone advise on what the issue might be? Thanks in advance