Hi Tom,
If you run a business as a sole trader, then yes, if your business is in debt and cannot repay it, the creditor can go after you. However, they can only go after your personal assets and your share in the house (if shared with your wife).
If you incorporate the business (i.e. form a company), then this will have considered a "separate person" from you. If this case, if your business owes debts, the creditors cannot then recover money from you unless you have personally guaranteed the creditor, put personal assets down as security or owe a liability as a director. However, the costs of incorporation is higher.
If you transfer the house to your wife, this might protect the house, however, there may be costs involved in the transfer (e.g. CGT event). However, a creditor may not agree to loan you money unless you have assets securing the funds (e.g. mortgage over property).
Most online startups are incorporated, given the high risks involved. If not, even if you transfer the house to your wife and your house becomes safe, the startup may force you into bankruptcy (which is not desirable) or you could be personally liable for offences committed by the startup.
