Most radios sold these days are open from 136-174Mhz. You (when licensed) may only transmit on the allotted frequencies for your license class--don't forget about bandwidth (it's in the study guide). However, in an emergency, you may transmit on the frequency that is most likely to get your message through (also in the study guide).
You are absolutely free to spend your $$ the way you want and this is just my 2 cents (feel free to give me back 1 1/2 cents if you wish). I would not buy that radio. I would (and did) buy a Baofung handheld radio on E-Bay for $40. It's disposable (meaning so cheap you won't cry if you break it) but functions quite well and will give you plenty of use where you live. You will be able to pickup and learn lots since there are tons of repeaters near you. Thousands of these have been sold and they make great backup radios.
Next, consider the TYT TH-9800 for mobile or base use. Again on E-Bay for around $250-275. It's a quad band radio so you will have plenty of room to grow into this radio. There are 10M FM repeaters in Dallas as well as plenty of 2M and 70cm. It has a low power draw so a 15 amp power supply would be perfect (try not to load your power supply over 50% of it's rating--this radio draws 8.9 amps). I recommend a Comet GP-15 tri-band antenna for the 6m, 2m, and 70cm bands. Then get or make a double bazooka for 10m and mount in an inverted "V" and use a duplexer to put them onto a single feed line and you are done--except for the General license to use all the bands (thus the grow into part). For the extra $100 or so bucks you get 4 radios in one--and it's a dual radio, meaning left and right side work at the same time so you can hear two stations at once--and lots more. I love mine and want another for the car. There is NOT a quad band antenna available that works--you will find them, but they are junk. For a car you should use only 2m and 70cm--you could get a 10m and 6m and use a duplexer but having three antennas would be ostentatious.
Again, just my 2 cents. Ask 5 hams a question and you will get 5 different answers (all will probably be off topic and about you spending more money).