Would appreciate advice on which of these I can uncheck safely. Image attached (I hope!).
Thanks.
It's all up to you as long as your system starts and then works well.

Just my opinion, uncheck:
- RAID event <- I'm using RAID and have this unchecked, if I need it I launch manually
- Adobe Acrobat, it'll come back on though after an update
- Cyberlink
- Dell Support
- Live Central
- Microsoft Office
I also disable some services i never use, like Office Groove, CP -> Administrative -> Services
I have lots of stuff installed, but only 45 processes on start .