Sorry Carol - I went away to research how iPlayer stores files and forgot to reply.
The easiest way is directly if your PC has a video output that your TV can use so it's time to explore round the back of the telly (armed with torch and reading glasses if you're my age) and and see if it has a video socket that looks the same as one on the PC. Most modern computers have VGA, DVI and/or HDMI outputs and most current flat-screen TVs have HDMI and either/or VGA and DVI. If there's a common one HDMI should be your first choice for quality, followed by DVI and VGA. If you use the latter two you'll also need an audio lead. If there isn't a common connector then some can be used with an adaptor, for instance DVI-HDMI or DVI-VGA but it might be worth getting advice from a computer shop on this.
If connecting the TV to the computer isn't an option then a possibility is to capture the iPlayer files in a portable format like MP4 as the WMV format is locked so it can only be played on the computer which downloaded it. Look at something like get_iplayer which will capture the files and convert them to MP4 so you can copy them to a USB memory stick and play them on the TV using a media player or a DVD or Blu-Ray player that can play from USB storage. You'll need to google get_iplayer and find the Windows or Mac instructions and follow them very carefully as it's about as user-friendly as a cornered rat but once it's working it works very well.
Out of curiousity what's your HD Media Player? Hisense?