Having just done that ... because I replaced the spinning rust in a ASUS U52F (Arrandale i5, 4G RAM) with a bigger SSD ... the real question is whether you want to dual-boot or not. I went for dual-boot. In that case, install Windows first (I did a clean install from media) and get everything working there (plan on an hour or more spelunking in the settings to lock things down more or less, from a clean install, plus installing any applications you want). Then use disk management to shrink the Windows partition to make space for Linux (I had the luxury of a 1TB SSD (one of those 1TB Sandisks that Tom's advertised last week) so I gave Linux 350GB; the old hard disk gave each about 250GB).
If you're installing Linux only hopefully you skipped to here. Then install the Linux of your choice (I used Mint 19 MATE). A well-behaved one will ask if you want to go side-by-side with Windows and install a good compromise package of root, swap, and home for dual-boot if you so choose. Full control over how everything is allocated is also available. Both sides work fine, and the SSD is so much faster than the old disk that it's like a new computer. Mint installs most of the basic stuff you would want (Libreoffice, Firefox, VLC, Thunderbird, etc.) that in Windows you have to install separately and fight with the system to make default over the MS junk.
BTW, Intel eventually did issue microcode updates for my ancient i5, so both Windows and Linux run it fully patched for the initial Spectre variants and Meltdown.
As far as speed is concerned, before the SSD, Linux took much longer to start up than Windows 10 Home, and had occasional hangs in operation. But overall it worked OK. With the SSD, both start up very quickly. Windows seems to shut down more quickly. In operation, they're similarly fast, but Windows needs more RAM for the system - Windows 10 1809 uses about 1/2 of my installed RAM (3.6GB available), while Mint 19 uses about 1/4. For some applications, that might make a difference between just being able to start it and actually using it.
The one annoyance that I haven't gotten fixed yet - the registry patch that is recommended for Windows doesn't work in mine - is that Linux uses UTC time and adjusts for the timezone in software, while Windows wants local time in the computer's RTC. Several other approaches are out there, including having Linux use a local-time clock (need to hunt that down again). Otherwise, it's interesting comparing the systems on the SSD - both are very peppy now, so it's almost a tossup - except, which one is open source?