@tdockery97 said, if you do it correctly, then no risk. Linux is absolutely safe, stable a ton than M$ windoz, and practically Virus free. It installs easily with sin xp or win 7. Linux needs ext3 or ext4 file system but can read and write FAT 32 and NTFS file system. Still do not install any Linux on NTFS. Linux has captured 70 % market share in servers. Companies like Google, Yahoo, amazon have linux servers, whereas companies like intel invest heavily in Linux. This sums up on stability and security of Linux. Mint forum is extremely user friendly and advanced users whole-heartedly help end users and newbies like you and me. there i als IRC chat, where you can get quicker answers.
For advantages of Linux, Out of my limited understanding, I have pointed out simple advantages in this post.Why Should I use Mint or any other linux?
I strongly recomend you to read manual BEFORE installing. Seriously consider this advise. Generally, people refer to manual only incase of emergence. Linux is not an app, but a new OS.
First you have to install windows and then any other linux distro. Before installation, back up your data
to external device like DVD or preferable external USB drive.
I will assume that you have no experience with Linux. I am not a pro, but I will try my best to explain you.
Try following things.
1. Linux Mint or most of Linux distros (distributions) have feature called as LIVE CD. Download the ISO file. Download MD5sum, which is a unique serial no (dont worry, it's all FREE). Md5sum is used to verify ISO file. In case the file is broken or slightly modified, Md5sum will change. Download winMd5Free. Open the software, browse that location of downloaded ISO file. After ISO file is selected, software will automatically calculate. Open md5sum in notepad (some Linux distrodisplay the no directly. In this case, copy md5sum and paste in the software. Click verify. If verification is successful, you can be assured that the file is genuine and error free.
Proceed ahead to burn ISO. to CD/DVD or to usb.
2. Burn ISO, many burning tools like Nero automatically identity ISO files and burn them properly. Just select the option to burn image and locate ISO file.
Hope this helps.
To burn in (empty) USB pen drive, use unetbootin. Insert USB drive open unetbootin and select option ISO file and locate the file. it detects USB automatically. Click burn and it will do the rest. USB drive can be reformatted under windows or you can simply delete everything and things are back to normal. I prefer USB since it is faster than DVD.
3. Reboot PC. Enter into BIOS and change boot order so that CD/DVD is first option. In case of USB, enable USB devices and enable prefer USB on startup. Save an exit.
Keeping USB attached or CD/DVD inserted , reboot.
4. unetbootin will load/. Select live cd option. Linux will load. Have a feel if Linux Mint. Check weather everything is working properly like sound internet connection, etc etc. after you feel comfortable, you can install.
You can run any Linux Distro inside windows. There is a program called Oracle Virtualbox (95 mb). You can install any Linux (or even windows XP / 7) inside the host OS (installed OS, min most cases windows). Guest OS will run inside virtualbox, which runs as any other software inside your main windows OS. It is very fast and you can do everything as if Linux is installed on your hard drive.
To explain virtualbox installation is beyond my pay grade
I strongly recommend you to try any Linux Distro inside Virtualbox before going for Dual boot.
If you are going for installation, please consider reading Considerations before you install
Hope this helps.