Yes it would be.
There's a few things I'd generally take into account
Firstly, whether there's an appropriate slot. A laptop may use 7mm or 9mm thick 2.5 inch drives (tho in some cases its plausible it could be purely msata or emmc). A 7mm drive would fit in the place of a 9mm drive but not vice versa. In this case its definately 2.5 inch sata and more likely to be 7mm thick rather than 9mm thick.
Since the crucial drive is compatible, the samsung should be. Most modern consumer SSDs are 7mm so they should be the same form factor
Electrically, both drives are sata III (and I believe the laptop in question is based off the Ivy Bridge platform) and so it should fit.
Only thing I'd get tripped up by is if dell chooses to attach a 'shim' between the drive and the connector on the desktop. If your old drive dosen't look like it has a sata connector, it may have a removable piece in front.
SATA drives are such common commodity parts these days that if the physical form factor matches, any one of them can be swapped for another model with no issues whatsoever