South Korea is a great place to visit. People tend to be very friendly, the alphabet is phonetic, food is good and everything is excitingly foreign! Don't forget your phrase book though.. English is not widely spoken. This was my 3rd trip to Korea, and it was an opportunity to catch up with Soosun's relatives, improve my pitiful Korean and see some interesting areas.
Should you happen to go to Korea with a partner, I would recommend staying in 'motels'. They are around 30,000-40,000 WON in most places per night, are conveniently located near transport and generally have nice rooms. Despite their reputation as love hotels, they are often more comfortable and cheaper than other alternatives. Don't be surprised, however, if they don't ask for your name, and require payment in cash!
Also, visiting the local jim-jil-bung (sauna) is an experience not to miss. They are generally open 24h and provide showers, sauna rooms, hot and cold pools, massage and general sleeping and relaxing areas, as well as funny coloured clothes to wear while you are there
Some of the fun stuff I did this trip was catching up with friends and relatives, walking around fortresses, going to a hot spring spa, doing a little caving, taking in some amazing scenery and going skiing.