Help/advice MCO-BOS-LHR

It's a special birthday for me next month and after being totally indecisive about where I wanted to go (if anywhere) I decided I wanted to go to Orlando for some relaxation and retail therapy.
I wasn't doing anything but UC but there was a distinct lack of availability direct unless I wanted to pay nearly as much for Y ticket as previously paid for UC. Managed to get Z fares direct out of Manchester on my actual birthday (a little bit further for us than Gatwick but not much) but the return with a combination of the best price and connection timings was inbound via BOS to LHR. This is Delta First Class/VS UC on VS4234/VS12
I've never done this route before so have a few questions.
Hopefully 3 hours in Boston will be OK and time enough for a visit to Boston Clubhouse?
Presume we can check bags through to LHR at the Delta desk in MCO and use the Delta lounge?
Can I do online check in with Delta and then separately with VS. I have already allocated seats on both legs.
I intend to have at least 4 bags (2 each) for the return, am I ok allocation wise on the domestic leg and will they be checked through?
Sorry, the questions to some maybe fairly basic but any help or other advice on terminal gates etc. will be appreciated.
Jilly
I wasn't doing anything but UC but there was a distinct lack of availability direct unless I wanted to pay nearly as much for Y ticket as previously paid for UC. Managed to get Z fares direct out of Manchester on my actual birthday (a little bit further for us than Gatwick but not much) but the return with a combination of the best price and connection timings was inbound via BOS to LHR. This is Delta First Class/VS UC on VS4234/VS12
I've never done this route before so have a few questions.
Hopefully 3 hours in Boston will be OK and time enough for a visit to Boston Clubhouse?
Presume we can check bags through to LHR at the Delta desk in MCO and use the Delta lounge?
Can I do online check in with Delta and then separately with VS. I have already allocated seats on both legs.
I intend to have at least 4 bags (2 each) for the return, am I ok allocation wise on the domestic leg and will they be checked through?
Sorry, the questions to some maybe fairly basic but any help or other advice on terminal gates etc. will be appreciated.
Jilly