There is no way to delete your account. At least not without admin help. And, as far as I know, this has only happened in extremely rare cases.
I dont really mind my account remaining on here but the issue being my IP address being stored/logged could cause me trouble in the future. So does deleting my account remove all the stuff I posted?
Your IP addresses are not stored/logged indefinitely. I don't know the exact information by heart, but I think that all stored IP addresses of members are deleted after a certain period of time.
If not, does deleting this account disconnect this account from those things posted? Or is it still stored/logged? In which case the best I could do is simply remove everything I can from what I posted. I honestly would like to keep those things up... but... Idk if it would still be connected to this account, which was connected to my real IP at one point. Idk.
Third-party sites have already archived everything, so you will never be able to delete everything, even if you delete all your content from this forum.