How good idea would it be? I just bought this catera sprots, I am a big fan of synthetic fluids, I pretty much have used it on all my previous cars and got atleast out about 200K with out any major/minor repair just regular tuneups only. Now I don't know any thing about this car's history and mechenics. would it be a good idea to have a caddi breath little solvent in oil and switch to synthetic?

You didn't tell us anything about the car. What year? How many miles?
Generally, I run synthetic in my cars. You can run into issues if the car has been running conventional oil for 75k+ because the solvents in the synthetics will sweep away the deposits that were sealing the gaps where the seals had dried out. So, you might end up with leaks.
As for an engine flush, I think they're a waste. If you want to change oils, there's no need to flush. If the engine is old, you might cause problems because things have dried out and become seated on the deposits. New motor, why bother? Just change the oil and you're set.

Yeah, just do synthetic oil.. no flush, dont need any additives. We put synthetic in our Catera right after we got it.

You didn't tell us anything about the car. What year? How many miles?
Generally, I run synthetic in my cars. You can run into issues if the car has been running conventional oil for 75k+ because the solvents in the synthetics will sweep away the deposits that were sealing the gaps where the seals had dried out. So, you might end up with leaks.
As for an engine flush, I think they're a waste. If you want to change oils, there's no need to flush. If the engine is old, you might cause problems because things have dried out and become seated on the deposits. New motor, why bother? Just change the oil and you're set.
Carfax says Car was a leased vehicle through cadillac at first owner then owner purchased it and traded it in. I am the second one with 40K miles on it.

At 40k, you have nothing to worry about. Engine is just well broken in. No deposits to clean out.