Be very careful - you may be in danger of being sold a pup - and this is a sales process, not independent altruistic advice.
If you take the first option there is probably nothing to stop them coming after your redundancy money as well (when you get it); also it is quite normal for the IVA to include a requirement to re-mortgage in the fourth year to release equity, or for it to be extended for another 2 or 3 years if this can't be done.
I think it is pretty unlikely that creditors will accept a proposal that writes off about 75% of the debt - this used to happen sometimes but a lot of creditors have become much more reluctant to agree anything like it. This is particularly the case because you have a house & they can - if they get a CCJ & you default on it - get a charge put on it, which secures their debt. NOTE: Above is based on your saying about 75% would be written off, but your figures don't stack up. Over 5 years you would pay �15K, which is 38% of the �39K you quote. If the figures you are quoting are what the firm has given you, it seems maybe to imply a rather shoddy slipshod approach, which is not a good thing when dealing with this type of issue.
Your second option is, on the face of it,somewhat better. You would pay 32% but its over & done with much more quickly - provided it is absolutely clear they cannot add in anything about the house.
If you want to go ahead read and study the proposal document extremely carefully and make certain you fully understand it. If there is anything at all you are not totally clear about query it, but don't rely on verbal information from the firm. Get all your queries properly explained in writing.
It would probably be a good idea for you to contact a free debt advice agency - such as CCCS (see website) - and go over everything with them before making a decision.