You probably need to boot it in safe-mode. (1) With the console off, press the power button and hold it down. (2) Continuing holding the power button until it powers back off. (3) Push and hold the power button again, causing it to beep, then double beep. (4) Finally, release the power button and you should get the screen with the different options. If that doesn't work, please try what I listed in the comments, then give me an update.
You'll need a USB that's correctly formatted, and has a bootable version of the desired operating system. (1) Windows 10 (2) Windows 7 (3) Linux (7 Best Versions) Most importantly, you'll need to ensure that your BIOs are set to boot from a USB drive. (If you're running off a solid state drive, with Windows 10 in particular, it can be tricky to get to the BIOs menu -- fortunately, that shouldn't be an issue with the system you're using, unless an SSD was installed afterwards) You can also diagnose certain issues and troubleshoot by using a bootable toolkit, in order to see if there's damage to the hard-drive or file system. However, if you never see any text display on the screen during boot-up, then it's likely to have much more extensive issues than just the operating system, or hard-drive. Best of luck.
Sounds like the standard symptoms resulting from the bad capacitors which plagued a number of Samsung TVs. There was even a lawsuit that required them to fix the issue free-of-charge -- but it's no longer in effect. If your TV matches any of the following models, then it's most likely what's causing the issue ... (1) LN-T******/XAA (2) LN**A******XZA (3) LNS4041DX/XAA (4) LNS4051DX/XAA (5) LNS4052DX/XAA (6) LNS5296DX/XAA ... even if it's a different model, it could still be the direct cause. It's not horribly expensive to repair, and easy enough to do for anyone who's decent with a soldering iron. (1) First, the back of the TV will need to be removed. (2) Verify that there are one or more bulging capacitors and identify the values of them. (3) Order capacitors with identical values online. (4) Then, change them out. Once they're replaced, it should work like new again. Best of luck.
The vertical lines are most likely due to connections with the data ribbon leading to the screen. I've often seen it happen to units that were left in hot cars or attics. Here's a great guide, from RetroFixes.com, that will, hopefully, help return the screen to normal ... Once you have the unit apart, you'll be able to line up the screen again. Just be sure to verify that it's straight before completely screwing it back together.