So my Discovery is making a weird noise a mechanic checked it out and said it is the catalytic converter .....i was thinking of taking it off and putting a direct pipe on it will this damage the vehicle in any way would it still run the same and will it take off the noise

 

what is it doing? cause the catalytic converter will not allow the vehicle to work properly without it.

if the shield is damaged then just take it off. its fine without it. they eventually rot off. if the catalytic converter flange bolts are damaged then install new ones. if you are uncomfortable with anything then take it for a second opinion. You mechanic is probably completely wrong or just trying to upsell you extra stuff.

 

If it's a rattling noise it could easily be a converter failure. Get underneath while the vehicle is running and see if it's coming from the cat, it's not that hard to diagnose.

Do whatever you like, but for the record this whole "cause the catalytic converter will not allow the vehicle to work properly without it." thing is completely untrue.

 

If you remove the cat you must remove both of them, and you will have a check engine light and you will not pass inspection if you have it in your state.
You can have a universal cat welded in for about $100 installed at a local muffler shop.