Yes, you can place the Dell components in a new case with no issues. But the PSU may be a problem. Awhile back Dell used a proprietary PSU and motherboard 20/24 pin header. Using a std PSU would cause major circuit issues. I don't know what year your 530 is, so it's hard to say if you can use a std PSU. It's been several years since Dell went back to std PSU/mobo header blocks, so you may be OK with a std PSU. I would contact Dell and ask if std PSUs are OK to use with your board.
That ended with the introduction of the Pentium 4
Only thing that may be a concern is compatibility issues with certain power supplies, the Corsair TX650v2 doesn't like the Studio 540 for some reason, the HX620 worked fine