First custom PC build (Q's)

Not really, except for programs that don't generate registry entries (World of Warcraft comes to mind) probably 99% of them would need to be installed again.

ignatzatsonic said:

It might matter if the old drive was connected while you were installing Windows to the new drive. Normally, you would not want the old drive connected because the Windows installation disc might try to put some files on the old drive and you would want all Windows files on the new disc.

Is that what you mean?

Yes, I know what you mean. It's OK, the main purpose of keeping it was for videos and pictures. I just wanted to know if all my recent programs would work.
So, if I connect the drive, and copy and paste all the files I want, would it be safe to just...delete everything on that HDD?

MadSupra354 said:

ignatzatsonic said:

It might matter if the old drive was connected while you were installing Windows to the new drive. Normally, you would not want the old drive connected because the Windows installation disc might try to put some files on the old drive and you would want all Windows files on the new disc.

Is that what you mean?

Yes, I know what you mean. It's OK, the main purpose of keeping it was for videos and pictures. I just wanted to know if all my recent programs would work.
So, if I connect the drive, and copy and paste all the files I want, would it be safe to just...delete everything on that HDD?

Yes, it would be safe, with this exception:

If you MOVE the files rather than copy them and your new drive fails tomorrow, you are out of luck with no backup.

So, I would copy them, not move them. And then use the new drive for a couple of weeks to see if it might fail early.

If it doesn't, then I would re-format the old drive and use it for whatever purpose.

I would confirm that the PC boots and works properly with the old drive disconnected.