Solved Temp folder takes up 42% of computer space

My problem is that the majority of my hard drive is filled with the Temp folder. My computer has begun to run slowly, so I thought cleaning it up a bit might help. I'm not tech savy what so ever, so I came here to ask for your advice. To begin with, here are some numbers:

Size of my C: drive: 287 GB
Size of my Temp folder: 121 GB (7581 files)

This means that the Temp folder alone takes up 42 % of the drive!

Address to the Temp folder: C:\Users\MyName\AppData\Local\Temp

So my questions are:
1. Can I safely empty the Temp folder? If I do, will the computer alert me if important files are about to disappear? Are there even any important files in the Temp folder?
2. Would a help program like CCleaner be of help in the clean up process, or is it uncessessary? Is deleting the files so straight forward that I don't need an extra program to help me?
3. The largest files in the Temp folder all begin with the letters "fla", for example fla2C91.tmp. I read some where that they are some kind of copies of files played with VLC Media player. Is this true? And if it is, I assume I can delete them with ease. These "fla" files take up in total almost 11 GB, so deleting them would help.

Thanks for your advice!

P.S. If it helps, my OS is Vista Home Premium 32-bit.

Welcome
Download the free ccleaner. Use it to remove alll the crap from your computer. It will free up a lot of space. In addition, use it once a month to stay problem free.
In addition download the free mawaarebytes to make a malware scan and make a full scan with your anti virus. You should be problem free,

In addition to what RichC46 said, you can run the Disk Cleanup utility from Windows Accessories and reboot ot empty the temp folder and the recycle bin.

Thanks to both! I used Ccleaner, and got rid of about 122 GB from my drive. I could call that "problem solved".

Thank you for reporting. We are glad that your problem was resolved

Hope you're having a nice Sunday Richard. You're answer was better than mine since I notice that the folder he was talking about was Local folder and the Disk Cleanup doesn't empty that folder. Most likely those are files from some installation. 122 Gb- that's a lot of files.