Budget is within walking distance from the Radisson, but there are no sidewalks and route A1A (the main drag) is quite busy.
My story - we rented from Budget at the airport and used the van to get around that day (Saturday before our Sunday Cruise). If you do not have a vehicle, there is really nothing to do except stay at the resort. Renting a vehicle you could go to Kennedy Space Center, shop or go out to dinner. We felt stuck when we stayed at the Radisson and did NOT have a car.
Any - we booked the Radisson Shuttle to go to the port on Sunday. We dropped the van off at Budget and they brought us back to the Radisson. This worked out well. Since we were going to WDW after the cruise, we had a town car pick us up when we got back to port, on thursday am.
This year we plan on having Budget bring us to the port. The Radisson is already booked and we have to stay somewhere else.