There is a trickle mechanism implemented so that, as long as units are in progress, the deadline can be extended quite generously. These tasks aren't really time dependant so there isn't a problem as such with returning late units.
Note that the time estimates in boinc can be quite a lot out before the unit is running. So they might not be as bad as seem once they get going.
Looking at the computer info, it looks like the processor is reasonable. The biggest CPU LLR unit is the Seventeen or Bust, and that'll take perhaps in the ball park of 2 days continuous running. The others are shorter but will still take a long time.
I'm not familiar with the CPU genefer unit, but suspect that could take a long time to run.
If you don't fancy waiting to see if they make it or not, you can just abort the units before they start. Before that, I'd suggest also going into the project options, where you can select which subprojects to run. The description indicates an average runtime for guidance. So if you prefer shorter units, you can just select those. Note that due to various bonuses, you generally get more credit per unit time if you do longer units.